INDIAN WELLS, Calif. — Serena Williams's return to tennis after a five-week break ended early with her retiring from the BNP Paribas Open because of a viral illness Sunday.
Williams raced to a 3-0 lead over two-time major champion Garbine Muguruza in their third-round match before dropping six straight games and the first set, 6-3.
''By the score, it might have looked like I started well, but I was not feeling at all well physically,'' Williams said in comments distributed by tournament officials.
During the changeover between sets, Williams called for a trainer. She went back out and lost the first game of the second set.