Roddick, who now stands outside the top ten for the first time since late 2002, fired eight aces and improved his record to 13-1 at Indianapolis, which he won in 2003 and 2004.

After taking advice and a training session from former great Jimmy Connors after losing to Briton Andy Murray in the Wimbledon third round, Roddick returns to tennis refreshed and revived.

"I feel really motivated, I can't wait to get out there and play," said the American. "I played solid throughout, I wasn't defensive at all. I accomplished a lot of things that I wanted to."

Roddick ended his one-hour master class against Paraguay's Delgado with a concluding ace on a night of super serving.

"I feel a lot more prepared for the next weeks," said the two-time Wimbledon finalist. "We had a lot of tough training (with Connors) last week."

Jittery defending champion Robby Ginepri overcame a double-fault on match point before finally carving out a 4-6, 7-5, 7-5 victory over Colombian Alejandro Falla.

It took the American defending champion another three games to prevail in two hours, 16 minutes over the challenger ranked 129.

Ginepri, seeded fourth, admitted that he froze on occasion as emotion took centre stage.

"I can't recall being this nervous in a match. I was worried about defending, but somehow I snuck through it," said the American who clocked 57 unforced errors.

"In matches like this, you really need the crowd support, they fire you up."

Ginepri managed 35 winners with Falla committing 61 errors.

The winner, 7-16 on the season, said he nearly ran out of puff. "I was absolutely exhausted. I wasn't playing close to my best tennis, but I found a way to win."

But 2006 has been a disappointment for Ginepri, beaten ten times in opening matches.

South Korea's Hyung-taik Lee halted the winning run of Mark Philippoussis as he eliminated the Aussie 6-4, 7-6 (7/4) in the first round.

Just two days after breaking a trophy drought, which had lasted for nearly three years, two-time, grand slam finalist Philippoussis was unable to make the quick switch from grass to hardcourt.

The 29-year-old who cut his ranking almost in half to reach 125th in the world as he beat Justin Gimelstob in the weekend final of the ATP Newport event.

"It was tough out there, very humid," the Australian said. "The balls were flying through the air and I couldn't get used to it.

"I had no feel for the ball and no control. I was struggling, but I felt Ok physically. I'm a little disappointed, it was a good chance to get some practice."

The loss in which Philippoussis fired a dozen aces, was balanced by first-round win from 35-year-old Aussie qualifier Wayne Arthurs, who put out Israeli Harel Levy 6-3, 7-5.

South African Wesley Whitehouse eliminated Gimelstob 6-3, 7-5 in the opening round.

Chile's third-seeded Fernando Gonzalez got off to a quick start after a bye, reaching the third round over American teenager Sam Querrey 6-3, 6-4 in just 67 minutes.

Gonzalez brought the 18-year-old ranked 200 back to earth after Querrey's Monday win. The 16th-ranked Gonzalez improved 24-13 on the season.

American holder Robby Ginepri was beginning his title defence against Alejandro Falla of Colombia.