ATLANTA -- Mardy Fish took a hit in his gradual return to full-time tennis, falling 4-6, 6-2, 7-5 to Michael Russell on Wednesday at the Atlanta Open.
It was only Fish's fourth match since the U.S. Open in September when he withdrew before a fourth-round match because of an irregular heartbeat.
Ranked No. 13 in the world last July, the sixth-seeded Fish -- the Atlanta Open winner in 2010 and '11 - fell to 1-3 this season. He's ranked No. 63 after his first match since losing in a lower-level ATP Challenger tournament in April.
"He played really well," said the 35-year-old Russell, ranked 85th. "He was coming up with 130 mph serves. I couldn't tell. Usually when somebody takes four months off, they're a little rusty. But it was really good tennis."
Russell took advantage of a rain delay -- the match began on Tuesday -- to make racket adjustments.
"It definitely helped me a little bit," Russell said about the delay. "I was able to change my string tension. I was pleased with the rain delay."
Seventh-seeded Lleyton Hewitt advanced to the quarterfinals with a deceivingly difficult 7-6 (3), 6-4 win over wild-card entry Rhyne Williams. The 32-year-old Hewitt, 64th in the world, trailed 2-6 in the tiebreaker before winning six straight points, and only broke serve in the second set in the deciding game.
While Hewitt and Russell stood up for the old guard, 19-year-old Chrisitian Harrison won his first match in an ATP main draw. A wild-card entry, the 373rd-ranked Harrison beat Alejandro Falla 6-1, 6-7 (7), 6-2.
Harrison will play top-seeded John Isner in the second round. Isner and second-seeded Kevin Anderson have yet to play.