Serena Williams started the defence of her Wimbledon title with a straight-sets victory over Amra Sadikovic but former world number one Caroline Wozniacki made a first-round exit on Tuesday.
Current rankings topper Williams was not at her best on Centre Court, but the 148-ranked Sadikovic was unable to take advantage as she was beaten 6-2 6-4 on day two.
Top seed Williams will now face fellow American Christina McHale in round two as she attempts to equal Steffi Graf's Open-Era record of winning 22 grand slams and seal a first major title since Wimbledon last year.
Wozniacki has plummeted to 45th in the world and the Dane fell at the first hurdle, losing 7-5 6-4 to 13th seed Svetlana Kuznetsova under the roof due to rain which forced play to be suspended on the outside courts.
Sixth seed Roberta Vinci recovered from a second-set blip to beat Alison Riske 6-2 5-7 6-3, while British wildcard Tara Moore beat Alison Van Uytvanck to reach the second round for the first time at the All England Club.
SERENA 'SUPER MOTIVATED' TO RETAIN TITLE
The Wimbledon title is the only major honour Williams still holds and the 21-time grand slam champion is determined to hang on to the Venus Rosewater Dish.
There has been talk of a potential changing of the guard following the 34-year-old's final defeats against Angelique Kerber at the Australian Open and Garbine Muguruza in the French Open, but Williams is itching for more success.
She said: "I would be lying if I said I feel fresh, but I don't feel fatigue. I don't think I feel fresh, but I feel real hungry, super motivated, extremely ready to do the best."
WOZNIACKI ROLLING WITH THE PUNCHES
Wozniacki missed the French Open due to an ankle injury and there was further misery for the 25-year-old when Kuznetsova sent her packing.
Kuznetsova will take on Moore in round two after breaking Wozniacki, who has never gone beyond the fourth round at SW19, four times and coming up with 23 winners.
Wozniacki said: "It kind of just sucks right now to be out of the tournament. There's not really much else to say. I mean, at one point you're just like, you know what, it has to turn, it has to go the other way eventually. I'm just going to take the punches I'm getting and just try and learn from it and try and move forward."
VINCI RELIEVED TO END POOR RUN
Vinci was beaten in the first round at Wimbledon in each of the last two years, so last year's US Open runner-up was relieved to return to round two at the expense of Riske.
"I'm happy. Finally I won a match here in Wimbledon. First round is always tough. My opponent today was a great player, especially on this surface." said the Italian.
"I played a good first set, a lot of chances to win the second set, then on third, 3-1 down, but I'm trying to play aggressive, trying to play my game. At the end, I was a little bit nervous. A lot of match points were saved. But I'm happy. Finally I won. I really enjoyed today."
World number 227 Moore is a surprise name in the second round following her 6-3 6-2 victory over Belgian Van Uytvanck, having also reached the quarter-finals in Nottingham recently.
Moore said: "It's amazing. Who would have thought before the grass season that I'd be where I am right now. I'm really grateful to the All England Club for giving me this opportunity.
"I think I've definitely worked really hard and I've definitely put in a lot of graft and I think it's paying off finally. I'm just really happy."
Moore's compatriot Johanna Konta was leading Monica Puig 6-1 2-1 when the rain came, while Eugenie Bouchard won the first set 6-3 and was a break up at 2-1 in the second against Magdalena Rybarikova.