It is a case of wait and see for Serena Williams as she battles a shoulder injury at the U.S. Open.
The world No. 1 has been nursing the injury since winning Wimbledon, but her quest for a 23rd grand slam tournament win got off to a perfect start Tuesday when she coasted into the second round past Ekaterina Makarova in straight sets.
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Looking calm, cool and collected — and, most importantly, pain-free — Williams recorded a 6-3, 6-3 victory in the opening round at Flushing Meadows.
"I feel OK," Williams told reporters after the match. "I mean, I didn't play as many matches as I would have liked to play, much on the hard court. There's nothing I can really do about it. I just have to get everything ready for here."
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Pressed further on the shoulder problem and when it is sore, the 34-year-old added: "Usually it's the day of, but as time has progressed, and this past week it's usually been the day after, so that's a really positive thing. I didn't make too many adjustments. I didn't hit them as hard as I normally hit them. I just went for more placement. I didn't go for the big 120s (mph on her serve), just the regular."
Williams has lost just once in the first round of a grand slam in 64 tries, and that record never really looked in doubt against Makarova.
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She showed no signs of the injury in winning 90 percent of her first serves. She also fired 12 aces as she earned a second-round meeting with countrywoman Vania King.
"I was pleased with my serve because I haven't been hitting a lot of serves at all," Williams said. "In practice, none of them were going in, so I was definitely excited about that.
"I knew today I needed to be focused because I've played (Makarova). She's gotten to the semifinals. She goes deep in majors. She knows how to play big matches on big courts. She's not intimidated. I knew I had to really come out today. It was my only option, really."
SISTER ACT IN OPENING ROUND
Venus Williams joined her sister with a winning start at the season's final grand slam, though in contrasting fashion.
Venus, the No. 6 seed, was forced to dig deep in her 72nd major appearance, eventually overcoming Kateryna Kozlova, 6-2, 5-7, 6-4.
Up a set and leading 3-0 in the second, Venus lost her way as Kozlova leveled the match, but the American veteran regrouped to book her spot in the second round.
My 18th first round win at the open. Wow! pic.twitter.com/giNJCCVadf
— Venus Williams (@Venuseswilliams) August 31, 2016
BEST OF THE REST PROGRESS
While all eyes were on Serena and Venus, Agnieszka Radwanska and Simona Halep were busy getting it done earlier in the day.
American qualifier Jessica Pegula was no match for Radwanska, who recorded a crushing 6-1, 6-1 win at Louis Armstrong Stadium.
No. 4 seed Radwanska — one of three players alongside Angelique Kerber and Garbine Muguruza who can dethrone Serena as world No. 1 with a U.S. Open title — was a class above, tallying just four unforced errors as she closed out the match in 55 minutes.
Halep, seeded fifth, was just as dominant against Kirsten Flipkens in a 6-0, 6-2 victory.
Canadian favorite Eugenie Bouchard entered unseeded and suffered an early defeat, tallying 46 unforced errors in her 6-3, 3-6, 6-2 loss to Katerina Siniakova as the 2014 Wimbledon finalist continues to struggle to contend for trophies.
ALL EYES ON HALEP, MUGURUZA, VINCI
World No. 2 Kerber opens her campaign against Mirjana Lucic-Bencic on Wednesday. Muguruza headlines the evening session as she faces Anastasija Sevastova. Roberta Vinci — the seventh seed and last year's runner-up — tackles local Christina McHale.