World record-holder Usain Bolt struggled to win his first race in nine months, clocking 9.91 seconds in the 100 metres to narrowly beat former record-holder Asafa Powell at the Golden Gala on Thursday night in Rome.

Powell timed 9.93 and European champion Christophe Lemaitre crossed third in 10.00.

As usual, Bolt got out to a slow start but unlike in most of his recent races he was behind until pulling in front with his very last strides.

Bolt had not competed since he was beaten by Tyson Gay in Stockholm last August, snapping the Jamaican’s two-year unbeaten streak. The triple Olympic and world champion then ended his season because of back and Achilles’ tendon problems.

Bolt didn’t celebrate as much as usual, waiting a while before kneeling down on one knee and pointing his arms diagonally to the sky in his usual victory salute - drawing a large cheer from the crowd of 47,732 at Stadio Olimpico on a pleasant evening.

Bolt will run again on Tuesday at the Golden Spike in Ostrava, Czech Republic. His next Diamond League meet will be in Oslo on 9 June, as he prepares for the world championships in Daegu, South Korea in August.

Since Powell set a world record of 9.74 in Rieti, Italy, in 2007, Bolt has broken the mark three times, the last being a 9.58 at the 2009 worlds in Berlin.

Yet another Jamaican, Steve Mullings, still holds this year’s best time – 9.89 set in Clermont, Florida, five days ago.

Bolt has beaten Powell in nine of their 10 meetings, with Powell’s only win coming in Stockholm in 2008.

Bolt added more muscle to his frame over the off-season to improve his starts, but he still had a much slower reaction time than Powell - 0.174 vs. 0.133, with Lemaitre at 0.129.

The wind registered plus 0.06.

In other events, American standout Allyson Felix improved her season-best time in the 400 while world champion Sanya Richards-Ross struggled to a fifth-place finish.

Felix clocked 49.81 seconds to improve on the 50.33 she ran at this year’s opening Diamond League meet in Doha, Qatar, this month.

Amantle Montsho of Botswana was the runner-up in 50.47 and Francena McCorory of the United States crossed third in 50.70.

Richards-Ross, who missed most of last year with a quadriceps injury, clocked 50.98. She shook her head in disappointment at the finish, although she improved on the 51.62 she clocked in Kingston, Jamaica, this month.

Felix won four of four Diamond League 400s last year but never broke the 50-second barrier.

Felix and Richards-Ross raced again 45 minutes later in the 200 but both were visibly tired, finishing fourth and fifth, respectively. Bianca Knight, another American sprinter, won in 22.64.

Blanka Vlasic, the 2010 world athlete of the year, won the high jump in a disappointing 1.95 - far off her personal best of 2.08.

This was the third meeting of the Diamond League circuit, with the next stop scheduled for Eugene, Oregon, on 4 June.

LJ Van Zyl of South Africa won the men’s 400 hurdles in 47.91 seconds to extend his impressive start to the season, while European champion David Greene of Britain was second in 48.24.

In Doha this month, Van Zyl beat last year’s Diamond League race winner Bershawn Jackson.