Updated

Roger Federer rallied past defending champion Tommy Haas 3-6, 6-3, 6-4 Saturday and reach the final of the Gerry Weber Open.

Federer, who lost to Hass in last year's final, is on course for his first title of 2013.

He's seeking his sixth title on grass in Halle, his favorite warm-up for Wimbledon. Four of Federer's seven Wimbledon titles have come after wins in Halle.

While Federer had 15 aces, Haas finished with nine double-faults. Two consecutive ones at the end of the third game in the final set gave Federer the decisive edge.

Federer will play either Richard Gasquet or Mikhail Youzhny in the final Sunday.