American top seed Andy Roddick toiled for more than two hours to overcome compatriot Todd Martin 7-6, 1-6, 7-5 in the first round of the Kroger St Jude tournament in Memphis on Wednesday.

World number two Roddick, runner-up at the $690,000 event last year, was fully extended by the world number 60 before sealing victory on his first match point after two hours, 20 minutes.

The tone of the tight match was established in the opening set, when an exchange of breaks led to a tiebreak secured by Roddick 7-2.

But Martin, with just two tour victories to his name this season, displayed the determination that has been his hallmark throughout a 14-year professional career, breaking Roddick twice in a quickfire second set to force a decider.

Crucially, Roddick's serve held up down the stretch.

Preventing Martin from earning so much as a break point throughout the third set, Roddick always kept his nose in front to build a 6-5 lead.

Martin was two points from levelling at 6-6 before Roddick surged through, winning the next three points of the 12th game to book a place in the second round.

Roddick, the 2002 Memphis winner and fresh from his first title of 2004 at San Jose on Sunday, cracked a total of 17 aces.

Including his two Davis Cup victories for the United States over Austria, Roddick has now won eight matches in a row since losing to Marat Safin the quarter-finals of the Australian Open in January.

In other first round men's matches on Wednesday, American former finalist James Blake beat South African Wesley Moodie 7-6, 6-1. Second seed Mardy Fish, beaten by Roddick in the San Jose final, overcame Frenchman Olivier Mutis 4-6, 6-3, 6-4.