LONDON, England (AP) —

Tyson Gay prepared for the anticipated chilly Olympics here by winning the 100 metres at the London Grand Prix in dreary summer conditions in the British capital yesterday.

The former world champion won in 10.03 seconds in a headwind of 1.2 metres per second, ahead of compatriot Ryan Bailey and Nesta Carter of Jamaica.

Gay’s main rivals for the July 27-August 12 Olympics were absent.

Jaamaica’s Asafa Powell was forced to withdraw with a groin strain to ensure he is fit for the games, and Olympic champion Usain Bolt sidestepped the event for tax reasons.

There was a lacklustre performance from home sprinter Dwain Chambers, who is preparing for the games after a lifetime Olympic doping ban for British offenders was lifted, failing to even advance from the heats.

In the 110 hurdles, Aries Merritt of the United States won in 12.93 seconds — equalling his own world-leading time this year —

after former Olympic champion Liu Xiang qualified for the final but withdrew with a back strain.

Home favourite Mo Farah enjoyed a comfortable victory in the 5,000 metres in 13 minutes 6.04 seconds, more than three seconds ahead of Collis Birmingham of Australia after upping the pace in the final two laps.

In the women’s 5,000, world champion Vivian Cheruiyot led home a Kenyan 1-2-3-4.

World champion Dai Greene was denied victory in the 400m hurdles, finishing second behind Javier Culson just like at the Paris leg of the Diamond League two weeks ago.

It helped Culson acclimatise for the Olympics.

There was, however, an unexpected British success in the women’s 400m hurdles. Perri Shakes-Drayton — ranked 21st in the event before the race —

won in 53.77 seconds, more than 1.7 seconds ahead of 2008 Olympic champion Melaine Walker, who was fourth.

European champion Irina Davydova of Russia was second followed by Kaliese Spencer of Jamaica.