NEW YORK • Serena Williams is "pain-free" as she embarks on winning a modern-era record 23rd Grand Slam title at the US Open, her coach said on Sunday.
The American tennis star, who is also chasing a record seventh crown in New York, has been struggling with a right shoulder injury which contributed to an early loss at the Olympics and sparked her withdrawal from last week's Cincinnati tournament.
"She has been pain-free for a few days now," coach Patrick Mouratoglou told ESPN on Sunday.
"The shoulder is still not 100 per cent but it's very close and she will find a way.
"She has a lot more to her game than just the serve - she has the power and mental strength.
"She wanted to play the Olympics in Rio, it was very important for her but the shoulder was killing her. She was just putting balls in play, but that's the past."
Williams suffered a shock semi-final loss at the US Open 12 months ago at the hands of Italy's Roberta Vinci.
She has an equally tough start to this year's event when she faces 2014 semi-finalist Ekaterina Makarova of Russia, the world No. 36, today.
Although Williams leads the Russian 4-1 in career meetings, Makarova surprised her in the fourth round of the 2012 Australian Open.
When asked how she rated her fitness, Williams said on Friday: "I'm really fit right now. I did serve pretty well at Wimbledon this year. I felt like I was able to hit aces when I wanted to."
The American has two records in her sights at Flushing Meadows, where she can overtake Steffi Graf's Open-era record 22 Grand Slam titles and also surpass the German's unbeaten 186 consecutive weeks at world No. 1.
But, with her fitness a concern, it may be tough for her to achieve those feats.
"There's a lot at stake for her," 18-time Grand Slam winner Chris Evert said on an ESPN conference call last week.
"She has a lot to fall back on if her serve is not working but it makes life tough for her and she wins a lot of free points on that serve.
"The women are only getting better and only gaining confidence when they play against her. There's going to be pressure on Serena."
Williams starts the US Open with just seven tournaments under her belt this season.
"I was with her in Rio," US Fed Cup captain Mary Jo Fernandez said on the ESPN call.
"She definitely was not 100 per cent physically with her shoulder."
Evert is tipping the second-ranked Angelique Kerber - who will become the new No. 1 if she wins her first US Open - third-ranked Garbine Muguruza, ninth-ranked Madison Keys and Simona Halep, a semi-finalist here last year, as the main challengers.
Surprise Rio gold medallist Monica Puig, unseeded in New York, "could definitely cause some damage," Fernandez said.
Much will depend on Williams' health and also her mental focus, according to Evert, who retired at the age of 34.
Williams turns 35 next month.
"We definitely had different games and I didn't rely on what she relies on (serve)," Evert said.
"But the fact of the matter is, when you get older, you have less days that you're motivated. You really have more flat days.
"It's so understandable to me that she has some scratchy matches during the year and she doesn't play well.
"But her high level of play is still higher than any other player."
US OPEN DAY 2
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