Third-seeded Fernando Verdasco fended off two match points and narrowly avoided a second round upset at the Legg Mason Classic on Tuesday, while Mardy Fish extended the longest winning streak of his career to 11 matches.

Second-seeded Andy Roddick had little trouble in his opening match, beating Serbian qualifier Grega Zemjla 6-4, 6-4 in the second round.

Three-time Washington champion Roddick never faced a break point against Zemlja and didn’t lose a point in his last four service games.

“I accomplished what I wanted to. I wanted to get in some rallies early, get my feet under me and move the ball around the court,” Roddick said. “Basically get back to playing clean tennis. The things that don’t necessarily show up on the stat sheet but win tennis matches.”

Roddick fired only four aces but he never faced a break point against Zemlja and didn’t lose a point in his last four service games. He also took advantage of his breakpoint opportunities, converting all four chances.

“I was in control of my own service games, which was good,” Roddick said. “I didn’t dig myself many holes out there.”

In the final match of the night, fifth-seeded John Isner needed two tiebreakers to defeat Thiemo de Bakker, 7-6 (6), 7-6 (8).

Isner sealed the win with three aces in the second tiebreaker. He had 15 in the match.

The last time the two met was in the second round of Wimbledon. De Bakker won that meeting, which came a round after Isner’s record-breaking marathon victory against Nicolas Mahut.

Both Isner and de Bakker relied on a strong service game, with de Bakker getting nine aces of his own. De Bakker saved the only break point of the match.

Verdasco twice faced match point in the second set before coming back to beat Michael Berrer 4-6, 7-5, 7-6 (6). Fish, who is seeded 15th, beat Viktor Troicki 6-4, 6-3.

Verdasco trailed 2-5 in the second set before winning five straight games to level it at one set apiece. In the third-set tiebreaker, he briefly sat on the court in pain holding his left foot after losing the 12th point. After the Spaniard rose, he won two straight points for the victory.

Fish, meanwhile, has won his past two tournaments, in Newport and Atlanta. His last loss came in the second round at Wimbledon. He credited his recent success to a new fitness regimen, which led to him losing 30 pounds since undergoing knee surgery last September.

“You’d be surprised at how much easier you can move around the court with 30 pounds less,” Fish said.

Troicki double-faulted six times in the match, included three times in one game during the first set.

“He’s a fiery guy,” Fish said. “He’s a very hot and cold type player. He played very well at times and he played poorly at times. I was able to keep it steady.”

Also in the second round, fourth-seeded Marin Cilic defeated Denis Istomin 6-4, 6-2 and Xavier Malisse upset 12th-seeded Julien Benneteau 7-5, 6-4.

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