Serena Williams showed signs of that "looking to become the first woman since Steffi Graf to win all Grand Slams in a calendar year" pressure getting to her in the second round match against Kiki Bertens, before the famous Serena power and desire came through to help the world number one advance to the third round of the 2015 US Open.
Next up for the American is a third round clash against compatriot Bethanie Mattek-Sands and Serena knows she will have to serve a lot better than she did against Bertens if she is to move into the second week of the tournament.
Serena dropped ten double faults in her second round match against Bertens, with the American going back to the practice courts to work on her serve immediately after her 7-6, 6-3 win.
"I've done it often enough," Serena said of having a hit in the practice courts right after a match. "I've done it a few times, so, It's nothing new actually -- for me at least.
"I just got a little nervous. But, I've been doing totally fine. I've been completely relaxed, chill. I've been really, really fine. So I'm going to get back into the place that I was and I'll be fine again."
Serena will need to be fine too, to beat the seasoned Mattek-Sands, something the holder of all four Grand Slams is well aware of.
"Knowing that she's capable of having big wins kind of relaxes me because I know she's going to come out and I know what to expect," Serena added. "She's going to give 300%. She's a huge fighter.
"She has a great game, by the way. I know that will help me, that I have to start out strong if I want to stay in the tournament. If not, I can go on vacation."
Mattek-Sands beat another American – Coco Vandeweghe – in the second round to seal a third round place for the first time in her US Open career. The 30-year-old will go into this match with that nothing-to-lose attitude, and that could prove to be dangerous for Serena.
"She's playing great," Mattek-Sands said of Serena. "I mean, right now she's on a mission to get a record, and I'm here playing my game. I think it's going to be a battle out there. I'm going to do my best. Right now I'm giving myself the best chance I can to play well. That's all I can ask for."
Where to Watch Live
Serena Williams vs Bethanie Mattek-Sands is scheduled for a 7 pm local time (4.30 am IST, 12 am BST) start with live coverage in India on Ten Sports. The third round women's singles match can also be watched via live streaming online on Ten Sports Live.
Catch all the US Open 2015 action in the US live on ESPN, while the live stream option is on Watch ESPN. Viewers in Australia can watch Serena vs Mattek-Sands Live on Fox sports, while the action can also be live streamed on Foxtel Play.
Audience watching the match in the UK can do so on Sky Sports, while the online live streaming option is on Sky Go.