Unseeded Henman beat Wimbledon champion Roger Federer 7-6, 6-1 and the Swiss third seed's chances of ending the year as number one have now all but disappeared.

Against a tiring opponent, Henman played top quality serve-volley tennis.

The Briton has beaten three times French Open champion Gustavo Kuerten, seventh seed Sebastien Grosjean and now Federer here. Asked whether he had ever played better, Henman said: "Never, I've never played with such consistency.

"It's exciting to be in this position and it will be a big match tomorrow."

The other semifinal is an all-eastern European affair between Czech 14th seed Jiri Novak, who defeated top seed Juan Carlos Ferrero on Thursday, and unseeded Romanian Andrei Pavel.

Roddick, who took top spot in the rankings just 24 hours ago, was always in control on his own serve against Bjorkman and in one game in the first set won all four points with aces.

Bjorkman hung in there bravely before the American broke his serve in the 12th game thanks to two superb backhand passes from the baseline.

The second set followed a similar pattern although Bjorkman was a net cord away from gaining a break point in the 10th game. The tiebreak was a rout, however, the US Open champion winning it 7-0 and ending with 19 aces all told.

"I don't think there are many times you are going to play Jonas and not have a break point against you," said Roddick who has conceded just two break points in three matches here.

"Tim's always very tough, he's got such a great feel for the game. I think he's a very underrated athlete." The two are 1-1 in career victories.

Roddick's win ended a 30-year run of success in which Swedish men had won at least one singles title in every year since 1973.

The 21-year-old Roddick is putting daylight between him and Spain's Ferrero, world number one until his last 16 loss, ahead of the season-ending Masters Cup in Houston.

A Roddick win against Henman on Saturday would rule Federer out of the race for the year-end number one spot.

Free of pressure, Henman has played fluidly but he was on the back foot for much of the first set and saved two set points in the 12th game.

Federer netted a simple forehand with the opposite court wide open to give away the first and on the second Henman, scrambling back after being lobbed, turned and hit a blind backhand down the line which the Swiss hit long.

Henman wasted one set point in the tiebreak with a double fault but won it on his third. Federer, winner of six tournaments this year, collapsed in the second set once his serve had been broken in the fourth game.