John Isner, Nicolas Almagro reach Houston final

John Isner got his big serve working after a slow start to reach the final of the U.S. Men's Clay Court Championship, beating defending champion Juan Monaco of

John Isner's 57 aces in the tournament is just three short of the record set by Pete Sampras in 2002 :: Pat Sullivan/AP

John Isner got his big serve working after a slow start to reach the final of the U.S. Men's Clay Court Championship, beating defending champion Juan Monaco of Spain 1-6, 6-4, 6-4 on Saturday.

The fifth-seeded American will face Nicolas Almagro, the top-seeded Spaniard who needed only 58 minutes to beat American wild-card Rhyne Williams 6-2, 6-1.

Isner finished with nine aces for a tournament total of 57, three short of the record set by Pete Sampras in 2002.