MLB Top Prospects 2023: Best rookie fantasy baseball sleepers, breakouts for redraft, dynasty leagues

It seems like every year, the topic of rookies gets more and more talk time in fantasy baseball. And why shouldn’t it? Year after year the rookie classes add more and more value to fantasy baseball rosters and drafts. The 2023 MLB rookie class will be no different, as there are plenty of potential breakouts and draft-day steals for both redraft and dynasty leagues. That's why having a top prospects list on your cheat sheet is just as important as rankings, sleepers, or dollar values.

Below, Matt Selz from Fantasy Alarm breaks down his top-10 fantasy baseball rookies for 2023 and provides a sneak peek at his overall top 400 for both 2023 and beyond (which is why the rankings are slightly different than his top 10 for just this season). Before diving into the list, though, let’s set some expectations.

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Even with last year’s incredibly deep rookie class, that doesn’t mean all were fantasy-relevant players. Starting with the hitters, 69 hitters lost their rookie status due to either 130 at-bats or 40 days on the active roster. Of those, though, just 29 had at least 300 plate appearances, or roughly half a season's worth. Of that subset, just 13 hit better than .250 regardless of counting stats, and 14 were better than league average in OBP (.312).

2023 FANTASY SLEEPERS & VALUES:
Cs | 1Bs | 2Bs | 3Bs | SSs | OFs | SPs | RPs

We all care about counting stats, such as homers and steals, but nobody wants a hitter to tank their slash lines. As for the homer totals, if we take all of the rookie qualifiers into account, just 23, or one-third, reached double-digit homers, and just 12 reached double-digit steals.

So, what’s the conclusion? If you’re in a 12-team league, there’s basically only one rookie, at most, per team who is fantasy-relevant.

2023 FANTASY RANKINGS & DOLLAR VALUES:
Cs | 1Bs | 2Bs | 3Bs | SSs | OFs | SPs | RPs | Top 300

Looking at pitchers, 124 pitchers logged at least 50 innings while still having rookie status last year. That’s a lot. However, like hitters, not all were fantasy-relevant options. Of those starters, 13 had sub-4.00 ERAs. However, only six of those had K/9 rates over 9.0.

Of the 80 or so qualifying rookie relievers, just nine posted at least eight saves, with five cracking double-digits. There were plenty of relievers with good ratios and K-rates, but with only a smattering of innings, wins, and "solds," they weren’t of much use for fantasy baseball owners. So, just like with the hitters, there are a lot of shiny names but not all of them are useful for fantasy purposes.

We point all of this out to remind you that while prospects are always exciting and potentially valuable, you shouldn't go overboard with them in your draft, at least in redraft leagues.

MLB Top Prospects 2023: Best rookies for fantasy baseball leagues

By Matt Selz, Fantasy Alarm

1. Corbin Carroll, OF, Arizona Diamondbacks

We got a taste of Carroll’s skills last year when he came up for a 32-game stint late in the season. Oh, what a taste we got. He hit .260/.330/.500 with four home runs, 14 RBIs, 13 runs, and two steals along with nine doubles and two triples. Over the whole of the season last year between Double-A, Triple-A, and the majors, Carroll slashed .294/.403/.580 with 27 HRs, 100 Rs, 75 RBIs, and 33 SBs in 123 games. That slash line supports why he’s the top prospect in my top 400. What can he do this year, though? Well, he’s slated to be the leadoff hitter for the Diamondbacks, which will give him a ton of at-bats and chances to steal. Carroll could easily hit his .260 mark again while being a threat for a 20-20 year with 80 runs and 60 RBIs. If Carroll eases into the role and cuts his K-rate from 27 percent down to, say, 24 or 25 percent, his slash line will tick up a tad, too.

2. Gunnar Henderson, SS, Baltimore Orioles

Henderson is all the rage this offseason and has been shooting up draft boards. He should be. Henderson has all the skills to be a five-tool player for the Orioles, though it might not happen as quickly or dramatically as some think. The lefty-hitting SS jumped through three levels in 2022, going from Double-A to the majors and amassing a .289/.402/.511 slash line with 23 HRs, 113 Rs, 94 RBIs, and 23 SBs. To be honest, we’re splitting hairs between Henderson and Carroll as the top rookie, and it essentially comes down to which suits your team's needs more. Henderson should be hitting in the middle of the Orioles lineup, likely between Adley Rutschman and Anthony Santander, which should give him pitches to hit consistently. One thing to pay attention to is his position eligibility in your league, though. While he played SS in the minors and was drafted as such, he played mostly at 3B for Baltimore once he came up. In leagues that give a player a position for just five games played, Henderson will fit at both 3B and SS coming into 2023. The main difference between him and Carroll as the top rookie is whether you want an infielder or outfielder and whether you want a touch more power or speed. Henderson has a bit more power and Carroll has more steals upside.

3. Josh Jung, 3B, Texas Rangers

Jung was originally on my top rookie list last year before the shoulder injury. That injury robbed him of nearly all of the 2022 season. It also deflated his stats...to a degree. Over the 57 games he played between a rookie baseball rehab assignment, Triple-A, and the majors, Jung slashed .239/.287/.486 with 14 homers, 43 RBIs, 28 runs, and three steals. That doesn’t sound great, but keep in mind that the shoulder injury kept him from reaching some pitches he normally does and sapped some of the bat speed. That being said, if you extrapolate his numbers to a full 162-game season, they're 40 HRs, 122 RBIs, 80 Rs, and nine steals. Now, extrapolating isn’t the best way to look at stats, but it does give you an idea of what he’s capable of. The power with Jung has been his calling card for a while, and he should be in the 25-HR range in his rookie campaign with a .250 average. The strikeout rate should drop now that the shoulder is fully healthy. We’d prefer him to hit fifth in the Rangers’ lineup rather than the anticipated sixth spot coming into the season, but if he produces a 25-70-75-5 season, then he’ll be a top-12 third baseman.

4. Triston Casas, 1B, Boston Red Sox

It seems like it’s been a long time since we’ve been expecting Casas’ arrival to the majors. He’s been a top prospect for Red Sox since he was drafted and finally got a taste of things toward the end of 2022. It was not a great trial run, to say the least. He hit just .197 with a .208 BABIP and posted a 24.2-percent K rate, which is a career-high for a stretch that long. There were some good things, though. Five home runs and a 20-percent BB rate led to a .358 OBP and a .408 SLG. Posting a .766 OPS despite a sub-.200 average is impressive. He’s slated to be the starting first baseman for Boston from the jump this year, which should give him basically a full year of games to show what he can do. Casas has a ton of power that will play well not only in Fenway but also across the AL East. Expect him to pop 20-plus homers with a .245-.250 average. That’s enough to make him a valuable fantasy asset at a shallow position like first base.

5. Jordan Walker, OF, St. Louis Cardinals

The St. Louis brain trust hasn’t been cooling down any of the Walker hype we have this offseason. In fact, they basically said that as long as he has a decent spring, he has a great shot of breaking camp with the team. That’s high praise for a player who’s still just 20. The trick for Walker -- and the reason why he’s not slightly higher on the list -- is that there’s no clear spot for him on the Cardinals right now. Walker was drafted as a third baseman but has had to shift to the outfield with Nolan Arenado firmly in his way to the majors. In 2022 at Double-A, he played mainly in right field and racked up nine outfield assists in the 25 games played. When he comes up, he’s likely to play in left field at first with Lars Nootbar being an outstanding defensive right fielder. Defense is great, but it doesn’t help fantasy, right? So, what’s his offensive upside looking like? The power is real — like 75-grade raw power — and the speed is MLB-average. That’s an intriguing mix from a guy who’s 6-5 and 220 pounds. Walker’s projection will strictly come from how many games we expect him to play. If it’s less than 100, we’re looking at 12-15 homers with a handful of steals and just under a .260 average. If it’s more like 120-130 games, he could be in the 20-HR range with eight-to-10 steals.

6. Francisco Alvarez, C, New York Mets

Is there a hotter prospect being talked about right now, perhaps other than Gunnar Henderson? I think not -- and rightfully so. Throughout 117 games across three levels (though just a handful in MLB) in 2022, Alvarez left the park 28 times with 79 RBIs and 77 Rs while slashing .258/.371/.510 with a .882 OPS. That would be an impressive line for any position, never mind catcher. We all know how thin that position is in fantasy baseball, so adding another premium bat brings some serious value. The question is just how much we'll see of Alvarez in New York in 2023. The Mets are going into the season with Omar Narvaez and Tomas Nido at catcher, which should be more than enough to let Alvarez continue to mature at Triple-A. Remember, catchers often take longer to finish developing because of the intricacies of the position. The expectation for Alvarez is to come up midseason in all likelihood and that limits his upside for 2023 unfortunately. He should play enough games to hit seven-to-10 home runs with some counting stats, though he’s not a steals threat like some of the other young catchers are.

7. Grayson Rodriguez, SP, Baltimore Orioles

If it wasn’t for an injury causing him to be shut down in the second half of the season last year, we’d have seen Rodriguez in Baltimore. With that being said, G-Rod is an ace in the making. That doesn’t mean he’s going to be an ace this year, though. He has an arsenal of five above-average pitchers, and he mixes the pitches well to keep hitters off-balance. In 14 starts last year at Triple-A Norfolk, he posted a 12.53 K/9 (35.8-percent K rate) and 7.7-percent BB rate over nearly 70 innings. The ratios were also great with a 2.20 ERA, 2.04 FIP, 2.90 xFIP, and 0.93 WHIP to go along with a .177 BAA. All of those are elite. Rodriguez should compete for a starting spot in the rotation in spring training, but it’s likely to be in the back of the rotation for 2023. Baltimore was very close to the playoffs last year and figures to be again this year, which should mean we see Rodriguez up for 22-25 starts, assuming health. That should give him ample innings to have a solid ERA in the 3.75 range while striking out a batter per inning. That figures to make him an SP5 or SP6 option in fantasy baseball for '23.

8. Kodai Senga, SP, New York Mets

There were a lot of teams rumored to be in on Senga’s services, but ultimately the Mets came away with him on a $75-million deal. The numbers he put up in the NPB over his career were very impressive, including a career ERA of 2.42 and a 10.0 K/9 over 11 seasons. That being said, MLB is different, and most Japanese pitchers need an adjustment period when they come stateside. The main reasons for this are the five-day pitching cycle rather than the six-day schedule in Japan, the heavier and larger MLB ball, and the travel schedule. Senga is slated to be the No. 3 starter for the Mets this year behind Justin Verlander and Max Scherzer. That should benefit him somewhat, but we should still expect an ERA in the 3.65-3.80 range and about 9.5 K/9. However, don’t be surprised if they skip him in the rotation a few times to keep his arm fresh during the transition to the MLB style of play.

9. Masataka Yoshida, OF, Boston Red Sox

One of the two big-name Japanese imports on this list, Yoshida will get plenty of at-bats for Boston's rebuilding roster. The 29-year-old OF hit 21 or more home runs in four of his last five seasons in Japan while also hitting for at least a .321 average. That’s what’s been most intriguing about him — his combination of solid pop and contact skills. The Red Sox are hoping that will really play at Fenway Park and the rest of the AL East. I’m not so sure he’ll make such a smooth transition, though. Let’s harken back to Seiya Suzuki and his growing pains last year for the Cubs. Granted, there was an injury involved with Suzuki, but even when healthy, he needed time to adjust to the quality of pitching in the majors. The same will likely be true with Yoshida. The Japanese import should be in line for a .280-.285 average and around 15-18 homers. Boston is anticipating him to be the leadoff hitter, which will hurt his RBIs but help his runs scored.

10. Curtis Mead, 3B/2B, Tampa Bay Rays

Talent and skill-wise, Mead is right there with Josh Jung and Jordan Walker. So, why is he further down on the list than those two? He plays for Tampa Bay. While Tampa is a well-respected organization for developing players, it is also more patient with its future stars than other teams. He's simply less likely to be called up before the other two third basemen in this piece. In 76 games split between Double- and Triple-A last year, Mead slashed .298/.389/.532 with 13 home runs, 50 RBIs, 43 runs, and seven steals. In a full season, that’s a 28-HR, 107-RBI, 92-R, 15-SB pace, just for reference. Like most of their players, Tampa has been adding versatility to Mead’s profile in the minors, having him play a few different positions with 46 games at 3B, 20 games at 1B, eight at DH, and a few elsewhere. That will help with his timeline to come up, but the 22-year-old is likely destined for a call-up in the July range this year.

MLB Top Prospects: Potential fantasy baseball sleepers, breakouts for redraft, dynasty leagues

Note: These rankings are for 2023 and beyond, which is why the rankings are different than just the top 10 for 2023