Federer through after tough Blake test

Roger Federer reached the US Open semi-finals with a 7-6 (9-7) 6-0 6-7 (9-11) 6-4 win on Thursday, but it was far from easy against the battling James Blake.

Blake became the first person in the tournament to take a set off the world number one and despite falling behind 5-1 in the final set, the American fought back bravely before eventually losing it 6-4.

The defending champion will play Nikolay Davydenko in Saturday's semi-final.