Patrick Willis and NaVorro Bowman manned the two inside linebacker spots for the 49ers in 2013, boasting the best duo in the NFL. But injuries and suspensions have ravaged San Francisco's depth in 2014.
With what seemed like a luxury pick, the 49ers selected the highly productive-but-undersized Chris Borland, a linebacker out of Wisconsin, in the third round of the draft. Borland's size and lack of top-end athleticism pushed him down boards. But his physicality, activity at the line and vision has since pushed the 49ers back into the top echelon of NFL defenses.
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Like Willis: Physicality and activity at the line
Playing on the inside of a 3-4 defense puts pressure on inside linebackers to not only track the ball early in run defense, but also embrace contact to allow teammates to make tackles and force running backs away from their initial hole.
While Borland doesn't have great size or bulk, he does a fantastic job in attacking his block, staying low and playing with great leverage, which forces interior offensive lineman to win with feet rather than shear strength. It doesn't get reflected on the stat sheet, but Borland's willingness to embrace contact and disrupt the play's flow allows other linebackers and safeties to thrive around him.
Below is a simple example of Borland embracing an interior block, forcing the running back to hesitate and giving his teammate a chance to make the tackle (to which he also assists).
Along with attacking interior blockers, Borland's active motion and quick feet allow him not only to position for would-be blockers, but also navigate around them to attack the backfield. Rarely taking a poor angle to the interior, Borland does a great job picking his chances to evade blockers and attack the ball carrier without leaving teammates out to dry.
His anticipation gives him plenty of chances to make plays at or behind the line of scrimmage, like in the play below.
Like Bowman: Vision and timing in space
Similar to his ability to navigate blocks, Borland's vision and (more importantly) timing has directly translated from his Wisconsin tape to the NFL. With talented speed rushers on the outside (Aaron Lynch and Aldon Smith combined for 17 hurries against the Giants), the 49ers allow Borland to pick his spots as a rusher and win one-on-one matchups in space.
Without great size, positioning is key for Borland to win leverage battles and finish tackles. He does a great job diagnosing plays with active-yet-controlled steps, making high-level reads on play development and putting himself in the best position possible. Against the Giants, he was rarely out of position. Borland even was almost at plays too soon, potentially leading to bigger plays had he not finished tackles.
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Below is delayed screen in which Borland reads the quarterback, makes his drop steps, sees the linemen set up and attacks through would-be blockers to finish in the backfield. While the tackle looks great, it's the timing and control to which he explodes in his reads that set up the play.
Despite being the only on to have played under 300 snaps this year, Borland rates second among NFL inside linebackers, according to Pro Football Focus, only behind Carolina's Luke Kuechly.
With Bowman out for at least the next few weeks and Willis on injured reserve, the 49ers sure are happy they invested a top 100 pick in Borland. They may have expected him to merit the 77th overall selection, but the rookie has been crucial for San Francisco's defensive success since he entered the lineup.
And the current sixth place team in the NFC will need him to continue exceeding expectations if it hopes to secure a playoff spot.
Eric Galko is the owner and director of scouting at Optimum Scouting and OptimumScouting.com, as well as a Sporting News contributor. Follow him on Twitter: @OptimumScouting