By Sophie Brown BBC Sport at Wimbledon

Roddick has twice been a runner-up at Wimbledon

Two-time Wimbledon runner-up Andy Roddick saw off Thailand's Danai Udomchoke 6-3 6-4 7-6 (7-3) to make the third round of this year's tournament.

The American third seed had to fend off break points in both the first two sets against the world number 114.

Udomchoke finally broke through in the third to level at 4-4, but Roddick claimed the subsequent tie-break.

The 24-year-old will meet Spanish left-hander Fernando Verdasco in the third round.

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"It was an up and down match," admitted Roddick, who has always reached at least the third round in his six previous apperances.

"Mentally I was a bit up and down but I got through. But I feel like I'm playing the big points really well."

Top seed Roger Federer was 6-2 7-5 2-0 up on Juan Martin Del Potro before rain stopped play in their Court 1 clash.

The Swiss world number one is looking for his 50th straight win on grass.

Fifth seed Fernando Gonzalez had to come from a set down before beating Alejandro Falla of Colombia.

The Chilean dropped the first set but fought back for a 4-6 6-3 6-4 7-6 (7-1) win and will now play Serbian Janko Tipsarevic.

Twelfth seed Richard Gasquet ended the hopes of fellow Frenchman Nicolas Mahut in straight sets.

Mahut has been one of the surprises of the 2007 grass season after reaching the final at Queen's, but Gasquet beat the Wimbledon qualifier 6-4 6-3 6-4.