Defending champion Andy Roddick unleashed the fastest serve in U.S. Open history on his way to a 6-0, 6-2, 6-2 demolition of Scoville Jenkins on Tuesday as Maria Sharapova's tournament was almost ended at the first stage.

Roddick slammed down a 152mph bullet in his first service game of the night as he overwhelmed Jenkins, the USTA boys' under-18 national champion, who was appearing in his first tour match.

The second seed raced through his opening match in 72 minutes to set up a potentially tricky second round meeting with Spain's Rafael Nadal.

"I'm just glad to be back," Roddick said.

"I couldn't wait to start the match.

"I think it was tough for Scoville, but he gave it a good run and he'll be back. Hopefully he will look back one day and think it was a cool experience.

"I knew he was a little bit nervous, so I thought I would go at him and show him some early on. The serve surprised me, when I hit it I didn't really pay much attention but then I heard a few 'oohs' and 'aahs' from the crowd."

Sharapova arrived in New York billed as the new queen of tennis after her dazzling win over Serena Williams in the Wimbledon final, but she was forced to rough it against gutsy American Laura Granville, scraping a 6-3, 5-7, 7-5 victory.

The Florida-based Russian mixed sublime winners with a rash of unforced errors but showed real character when she served to stay in the match at 4-5 in the decider.

When a fierce first serve finally ended the contest after two hours, nine minutes of pulsating action, she breathed her huge sigh of relief and pumped her fists.

"Tonight was a very tough match, especially as it was my first big night match on Arthur Ashe. I was making so many unforced errors, I was out of it at times," she said.

NORMAL SERVICE

Earlier top seed and defending women's champion Justine Henin-Hardenne was given a scare by 15-year-old Czech qualifier Nicole Vaidisova when she fell 4-1 behind in the second set after taking the first 6-1 in 17 minutes.

Normal service was resumed as she won five consecutive games but the Belgian admitted the teenager, who won her first WTA tournament in Vancouver earlier this month, had proved a big surprise.

"I went to sleep a bit at the beginning of the second set and she started to play better, I wasn't ready for it," said the 22-year-old, who returned from a debilitating virus to claim the gold medal at the Athens Olympics.

Fifth seed Lindsay Davenport, who is one of the favourites to challenge Henin-Hardenne for the title, cruised into the second round with a 6-4 6-0 defeat of Slovakia's Lubomira Kurhajcova -- her 18th consecutive victory.

Another serious contender for the title, French Open champion Anastasia Myskina, was equally impressive, crushing Ludmila Cervanova 6-1 6-0 in 42 minutes to lead a total of 11 Russian women into the second round.

Eleventh seed Venus Williams also moved through with an unconvincing 6-3 7-6 win against Hungary's Petra Mandula.

SAFIN SUFFERS

In men's first round action Russia's Marat Safin, the 2000 champion, suffered his earliest U.S. Open exit in six attempts as the 13th seed slumped to a 7-6 6-4 3-6 6-3 defeat to experienced Swede Thomas Enqvist.

"I've not got enough confidence to beat these guys at the moment, coming to a tournament like this without any confidence is a little bit tough," a gloomy Safin said.

"To be honest I'm not feeling very happy with myself."

Last year's beaten men's finalist Juan Carlos Ferrero survived, just, although he will have to improve dramatically if he is going to make a similar impact this year.

The Spaniard spent four hours, 28 minutes on Louis Armstrong Court to scramble past Czech qualifier Tomas Zib 4-6, 7-5, 7-6, 6-7, 6-3.

Fifth seed Tim Henman overcame a painful back and 39 aces from giant Croatian Ivo Karlovic to advance, the Briton recovering from a set down to win 7-6, 6-7, 4-6, 6-4, 6-4.

Double Olympic gold medallist Nicolas Massu of Chile maintained his hot streak, blasting away Jose Acasuso of Argentina for the loss of just six games.

Thailand's Paradorn Srichaphan also cruised into the second round, coming from a set down to beat Victor Hanescu of Romania 4-6, 6-4, 6-1, 6-1.

There were several other seeded casualties on day two, including men's 24th seed Ivan Ljubicic who fell to Lee Hyung-taik of South Korea and Germany's Rainer Schuetttler who squandered a two-set lead against Italian Andreas Seppi.