The five-time Wimbledon champion has been sidelined with Sjogren’s syndrome, a disorder of the immune system, and was delighted to be back playing again.

“It was great to be back out there,” the 31-year-old said.

“It was definitely nerve-wracking, especially playing an opponent that I know how talented she is and first match back.

“But I was able to get a great start and settle in and play well.”

Williams dismissed the suggestion she may have considered retirement due to her condition.

She added: “I’m not at my worst anymore. So that helps, as well. Someone with an autoimmune disease definitely faces different challenges than other people, but it doesn’t mean you can’t be successful.”

Unseeded Williams will face third seed, and reigning Wimbledon champion Petra Kvitova in the second round.

“I think in some ways we play a very similar game,” Williams said. “Obviously she’s been playing very well in the last 12 months or so. It’s just totally a credit to her.

“I have had a lot of experience with playing well. I played all right today. I’m going into this just focused on executing my game and just trying my absolute best, which is the same thing she’ll be trying to do.”

Meanwhile in her first match since suffering an ankle injury in the Australian Open, former world number one Kim Clijsters was pushed before overcoming Australia’s Jarmila Gajdosova 4-6 6-1 6-0.

Other women’s first-round winners included Israel’s Shahar Peer, Sweden’s Sofia Arvidsson, Czech pair Iveta Benesova and Barbora Zahlavova Strycova, and Russian qualifier Valeria Savinykh.

Hungary’s Melinda Czink continued her strong run, having beaten Britain’s former junior Wimbledon champion Laura Robson in the final round of qualifying.

Czink beat Italian Alberta Brianti 6-1 6-2 to set up a second-round clash with Chinese eighth seed Li Na.

Holland’s Michaela Krajicek will tackle world number one Victoria Azarenka in the second round after beating qualifier Eva Birnerova 5-7 6-4 6-0.

Tour veterans Tommy Haas and Arnaud Clement made it into the second round of the men’s competition with victories over Guillaume Rufin and Dudi Sela respectively.

The 33-year-old Haas beat Frenchman Rufin 6-4 6-4 while Clement, one year Haas’ senior, saw off Israeli 26-year-old Sela 6-3 6-3.

Bulgaria’s Grigor Dimitrov was a 6-2 6-2 winner over Mikhail Kukushkin of Kazakhstan, while other winners included Robin Haase, Xavier Malisse, Nikolay Davydenko, Lukas Lacko and Lukas Rosol.

Former top-10 player David Nalbandian edged past Belgian Steve Darcis in his opener, the Argentinian surviving 7-6 (7/0) 6-4, while Portugal’s Frederico Gil had a fine 6-3 6-4 win over Brazilian Thomaz Bellucci, a player ranked 38 places ahead of him at 47th in the world.

Croatian qualifier Antonio Veic beat American teenager Denis Kudla 2-6 6-2 6-1, while Spanish qualifier Roberto Bautista-Agut ousted Italian Andreas Seppi 6-3 1-6 6-3.

There were also successes for Ivan Dodig, Alejandro Falla and Santiago Giraldo.

In the evening session, France’s Nicolas Mahut beat Chile’s Fernando Gonzalez 7-5 4-6 7-6 (7/3), a match significant for it being the last match of 31-year-old Gonzalez’s career.

The 2007 Australian Open runner-up recently announced he would quit due to injury problems, and world number four Andy Murray paid tribute to a player renowned as an exciting shot-maker.

“I think everybody would agree he’s one of the most exciting players to watch,” said Murray, who lost two of his three career matches against Gonzalez, including a French Open quarter-final defeat in 2009.

“He had a massive forehand, one of the biggest probably ever. He could hit winners from anywhere on the court. Great character. He’s quite up and down emotionally, but that’s something that made him fun to watch.

“I get on very well with him. He’s a really nice guy, too. So I wish him well with his retirement. He had a fantastic career.”