Roddick powers through

Andy Roddick kept the Stars and Stripes flying on Independence Day by completing a straight sets victory over Paul-Henri Mathieu.

Roddick, the only American in the men's draw to reach the fourth round, polished off the unseeded Frenchman 6-2 7-5 7-6 (8-6) after rain and a thunder storms had dragged the match into a third day.

But the Wimbledon third seed was given a fright in the third set as Mathieu was serving for the set but went to pieces at the crucial moment and Roddick survived another scare in the tie-break before closing out the match.

Mathieu, having slipped 2-0 behind heading into the third set, easily held his serve in the opening game and then stunned Roddick by securing the crucial break in the second.

The American was struggling on first service and Mathieu pounced, keeping his opponent pinned in the left corner before firing an impressive winner.

But it was not just Mathieu's brilliance doing the damage as Roddick was making a host of unforced errors that had been absent from his game yesterday.

Now Mathieu's serve had become impenetrable and Roddick waved his hands in frustration in the seventh as he continued to come off second best in most rallies.

But serving for the set, Mathieu's composure suddenly deserted him with two long forehands, an undercooked dropped shot and wide backhand allowing Roddick to break back.

The world number three had seized his opportunity brilliantly and the set went into a tie break.