Federer outplays Wawrinka to make final
Federer faces Kei Nishikori in Sunday's final after the Japanese's surprise win over world number one Novak Djokovic.
It was Federer's 10th win in 11 matches against his close friend Wawrinka, who trained in Basel as a youth.
The first set saw Federer break to 3-1 but Wawrinka broke back as he was serving for the set.
It went to a tie-break that ebbed and flowed until Federer took control, winning it 7-4.
Federer was far more impressive in the second set though, breaking his opponent twice and playing some of his better tennis in recent months.
He also showed his sportsmanlike streak when, after Wawrinka fell to give Federer two match points, he insisted on challenging the umpire's decision on his serve to bring it back to 30-30.
Federer went on to earn two match points, taking the second to set up a final against wildcard Nishikori.