Sloane Stephens made a spectacular return to grass as she knocked out two-time Wimbledon champion Petra Kvitova in the first round.
The American triumphed 6-3 6-4 over the 10th seed in an enthralling battle on Centre Court, with the roof open after the wet weather from earlier in the day had disappeared.
It was the 28-year-old's first appearance on grass since a third-round defeat to Johanna Konta in SW9 two years ago, but the former US Open champion quickly hit her stride and never looked back.
Earlier, second seed Aryna Sabalenka ended Wimbledon's two-year wait for tennis with a straight-sets victory over Monica Niculescu in the first round.
Wet weather saw a delay to proceedings on day one with no play on the outside courts possible in the morning.
But with the roof on Court One, the Belarusian was able to kick-start the tournament with a 6-1 6-4 win.
Sabalenka will face Britain's Katie Boulter next, and admitted that the victory was anything but a routine win.
She said: "I was really nervous to open Wimbledon and also be first playing on Court One.
"I was nervous a little bit because I haven’t played on the stadiums before but really happy that I won the match. The atmosphere was unbelievable."
Seventh seed Iga Swiatek claimed a first senior win at Wimbledon after beating Hsieh Su-wei 6-4 6-4 to reach the second round.
A junior winner of the tournament in 2018, the Polish right-hander broke her opponent at the beginning of each set to make a triumphant start to this year's Championships.
Victorious at the French Open last year as a teenager, Swiatek was back on Court One for the first time since she lifted the junior title at SW19 three years ago.
An early break against her opponent from Chinese Taipei was the perfect way to start a match being played under the roof following the early wet weather.
The 20-year-old made the most of that slender advantage and remained strong on serve to take the first set and the second followed a similar pattern.
While Hsieh was able to break back after dropping her serve in the opening game of the second set, the 35-year-old struggled to create further opportunities.
Instead Swiatek, still playing her shots and making numerous forehand winners, progressed into round two.
We've waited a while for this...@SabalenkaA and Monica Niculescu are out on No.1 Court to begin today's action 🙌#Wimbledon pic.twitter.com/uY1btV2NLL
— Wimbledon (@Wimbledon) June 28, 2021
Katie Swan was the first British woman to come through Wimbledon qualifying in 20 years.
But her stay at the Championships was a short one after a straight-sets defeat against experienced American Madison Keys.
Keys, a former US Open finalist and seeded 23rd, won 6-3 6-4.
Jodie Burrage's first Wimbledon experience ended swiftly with a heavy first-round loss to Lauren Davis.
The 22-year-old was handed a wild card in to her first main draw at SW19, but won just three games in a 6-2 6-1 loss to the American.
She spent less than an hour on court as Davis gave her the run-around, getting the job done in 55 minutes.
