Ryan Harrison found his second wind just in the nick of time.
The American, who is coming off back-to-back semifinal showings in Atlanta and Los Angeles, struggled in the second set against Mischa Zverev. Then Harrison turned things around for a 6-4, 1-6, 6-1 win in the first round of the Legg Mason Tennis Classic in Washington D.C.
"I started to get a little physically drained [in the second set] because of all the traveling," Harrison said. "Just getting used to the new time zones and everything. Then I got a second wind in the third set. I felt my energy level go up."
Harrison broke easily in the first game of the third set and didn't look back. Even though Harrison won the first set 6-4, he said he felt he should have won more convincingly.
"It was frustrating in the beginning just because I was returning pretty good too," Harrison said. "I [was] up love-40 at 1-2. I felt like I had opportunity after opportunity to get on top, and he was just hanging around. I never really got that break I was looking for."
Harrison did get the break at 5-4 to win the set, but Zverev came out on fire to start the second set and cruised to win the set 6-1.
Harrison will now play No. 3 seed Viktor Troicki on Wednesday in the second round. Harrison, who is currently ranked No. 82 in the world, said his goal is to be in the top 50 by the U.S. Open.
Other winners Tuesday included American Ryan Sweeting, who beat fellow American Alex Bogomolov Jr., 6-2, 6-4. Bogomolov has had a strong showing this summer and reached the semifinals in L.A. last week.
Sweeting said he was happy with how he served.
"I've struggled with my serve a little bit this summer, but today I had quite a few aces and very few double faults," Sweeting said.
Sweeting will play top-seeded Gael Monfils in the second round Wednesday.
Tommy Haas, who is coming back from injury, beat Amer Delic, 6-3, 6-2, in a first-round match. Haas just recently became an American citizen. He also became a father, as his wife actress Sara Foster gave birth to a girl late last year.
One of the game's rising stars, Grigor Dimitrov, rallied past Tim Smycek, 4-6, 7-6 (3), 7-6 (3). Flavio Cipolla and Michael Berrer also won first-round matches.
American James Blake defeated defending champion David Nalbandian, 6-2, 6-4.
Blake will play fellow American John Isner on Thursday in the round-of-16. Isner beat Tobias Kamke, 6-1, 6-3 on Tuesday night.