Serena in health scare

London - Diagnosed with a viral illness, Serena Williams pulled out of her Wimbledon doubles match with sister Venus after only three games  on Tuesday.

Serena, who lost in the third round of singles Saturday, looked out of sorts from the moment the pre-match warmup began.

It was an odd scene, as the 32-year-old American had trouble collecting tennis balls from the ball kids and whiffed on some practice strokes.

"I am heartbroken I'm not able to continue in the tournament," Serena said in a statement. "I thought I could rally this morning, because I really wanted to compete, but this bug just got the best of me."

Venus said: "Unfortunately, Serena has been feeling unwell for the past few days and she just couldn't play to her potential today. I'm really proud of her for trying, because we just love playing doubles together."

The start of the second-round doubles match against Kristina Barrois and Stefanie Voegele was put off for about 10 minutes while Serena sat in her sideline chair and was examined by medical staff, including a check of her blood pressure. At one point, Serena hunched over and covered her face with her hands.

During the delay, one of the Williams' other sisters, along with Serena's agent and her hitting partner, left their seats in the stands.

Eventually, the match began. With Serena serving in the third game, she was broken at love with four double-faults. One of the best servers in the women's game, she hit balls that bounced before reaching the net.

At love-40 in that game, chair umpire Kader Nouni took the unusual step of climbing down from his perch and walking over to speak to Serena. She then served another double-fault to trail 3-0.

Serena and Venus walked to the sideline holding hands, and Nouni announced to the crowd at No. 1 Court: "Ladies and gentlemen, unfortunately, Miss Williams has to retire."

Serena wiped away tears as she walked toward the court's exit.

Later, the Wimbledon referee's office and WTA said that Serena had a viral illness.

About 1 1/2 hours after leaving the court, Serena walked out of the All England Club, still wearing her white outfit, and with a tournament towel draped around her waist. She got into a car and was driven away.

Serena and Venus have won 13 Grand Slam titles together, including five at Wimbledon. In singles, the No. 1-ranked Serena owns 17 major titles, the most among active women.

"From the bottom of my heart, I thank all of the fans for their cheers and understanding," Serena said. "I look forward to returning to Wimbledon next year."