US Athletics Championships: Tyson Gay among 10 to go sub-10

Tyson Gay's 9.85 second clocking was fifth-fastest in the heats

Only six British men have broken 10 seconds for 100m - but 10 Americans achieved the feat in one night at their national championships.

During Thursday's four heats in Eugene, 2007 world champion Tyson Gay clocked 9.85 seconds - faster than any Briton in history - but was still beaten.

Remontay McClain, 22, led the way with 9.82 seconds, while 19-year-old Trayvon Bromell ran 9.84 as all 10 athletes to go under 10 seconds progressed to Friday's semi-finals.

The first three finishers in the final will qualify automatically for the World Championships in Beijing, which begin on 22 August.

The only Briton to break 10 seconds this year is Adam Gemili, who has run 9.97 twice - although on the first occasion with a following wind too strong for record purposes.

Though all of the sub-10 performances in the US trials were wind assisted - half of them beyond the permitted two metres per second - the obvious depth in American sprinting will fuel their hopes of threatening Jamaica's recent dominance.

Team USA finished second in the 4x100m relay at the 2012 Olympics but the form of Usain Bolt, who anchored Jamaica to gold in London, has come under scrutiny.

Britain's Linford Christie won Olympic gold in Barcelona in 1992

America's ease of finding sprinters capable of going under 10 seconds contrasts with the struggle Britain has faced since Linford Christie ran 9.87 in 1993 - a year after he won Olympic gold.

There have been six British sub-10 runs since - from James Dasaolu (9.91), Chijindu Ujah (9.96), Dwain Chambers (9.97), Gemili (9.97 twice) and Jason Gardener (9.98).

And while a repeat of the gold medal GB claimed in the 4x100m at the 2004 Olympics looks a long way off, even an American 'B' team could threaten the podium.