Olympic bronze medallist Bershawn Jackson ran the fastest 400 metres hurdles of the year on Sunday, then predicted an American sweep at the world athletics championships in August.

"Most definitely a sweep," said the head-band wearing Jackson after his victory at the U.S. trials in 48.03 seconds.

"We have the greatest hurdlers in the world. I don't think other countries in the world can compete with America."

The 2004 Olympic gold medallist Shawn Crawford sped to a wind-assisted 19.73 seconds in winning the men's 200, while world champion Allyson Felix claimed the women's race in 22.02 seconds to set up another U.S.-Jamaica sprint showdown in the Berlin world championships.

"That's the fastest my body has ever moved in its lifetime," said 31-year-old Crawford, whose non-assisted best is 19.79 seconds.

Dawn Harper backed up her Beijing gold medal with a wind-assisted 12.36 seconds in the women's 100 metres hurdles, but there was disappointment in the heptathlon when Olympic silver medallist Hyleas Fountain withdrew after five events with a neck injury.

CUT-THROAT

Only the top three finishers in the cut-throat trials and defending world champions qualify for the American team for the Aug 15-23 worlds.

Young collegian Johnny Dutch claimed second behind Jackson in the 400 hurdles with a lifetime best 48.18 with Olympic champion Angelo Taylor third in 48.30.

They will be joined on the U.S. team by world champion and Olympic silver medallist Kerron Clement, who has a bye to Berlin as the defending global champion. Clement finished third in the 400 metres Saturday.

World 100 metres hurdles champion Michelle Perry also took advantage of a bye and did not run the final after locking arms with hard-luck Lolo Jones in the semi-finals. The collision knocked Jones out of the race and the championships.

"That just threw me off balance," said Jones, last year's top-ranked hurdler who stumbled at the penultimate hurdle while leading the Olympic final and ultimately finished seventh.

Ginnie Powell and Damu Cherry will join Harper and Perry in Berlin.

Olympic silver medallist Christian Cantwell topped the men's shot put at 21.82 metres with Dan Taylor, world champion Reese Hoffa and former global winner Adam Nelson also making the team.

Crawford's team mates in the men's 200 will be Charles Clark, Wallace Spearmon Jr. and Tyson Gay, who as the world champion has a bye to Berlin.

Muna Lee, Marshevet Hooker and Charonda Williams will join Felix in the women's 200 at Berlin.