France's Roger-Vasselin prevailed over Isner 6-4, 4-6, 6-4 in one of the day's semifinals, using a decisive break in the third set en route to a hard-fought victory over the American favorite.
He'll be seeking his first career title Sunday against Latvia's Gulbis, who needed a third-set tiebreaker to bounce former Delray champion Haas 6-3, 4-6, 7-6 (7-2).
Gulbis -- the 2010 Delray winner -- emerged with the win after a 2-hour, 14-minute battle. He will be playing for his third career ATP Tour win.
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