Holder and top seed Roger Federer scored a comfortable 6-3 6-3 win over unseeded Spaniard Fernando Verdasco at the Hamburg Masters yesterday to ease into the semi-finals.
The Swiss world No 1, still without a major title to his name this year, was joined in the last four by closest rivals Rafael Nadal and Novak Djokovic.
The second and third seeds will play each other for a place in tomorrow's final and the in-form Serb will take over Nadal's No 2 world ranking if he wins. Federer will meet Italy's Andreas Seppi.
Djokovic brushed aside Verdasco's compatriot Albert Montanes 6-2 6-3 and Nadal thumped fellow Mallorcan Carlos Moya 6-1 6-3, while Seppi crushed the hopes of the home crowd by beating Germany's Nicolas Kiefer 6-3 5-7 7-5 in a three-hour thriller.
Four times a winner in Hamburg, including against Nadal in last year, Federer has played the 24-year-old Seppi just once, coming through a tight match at the Monte Carlo Masters last year in straight sets.
Djokovic has won the Australian Open and two Masters Series titles already this year and was far too good for Montanes, wrapping up the match in just 76 minutes.