MEMPHIS, Feb. 22 (UPI) --
Top-seeded John Isner
won his first-round match over Gilles Muller
Tuesday to advance at the Regions Morgan Keegan Championships in Memphis.
Isner battled his way to a 7-6 (7-1), 7-6 (7-4) triumph by serving 26 aces and winning 48 of 50 points.
Fellow American Ryan Harrison advanced Tuesday with a 6-3, 2-6, 6-4 victory over Jack Sock.
Other first-round winners Tuesday were Ryan Sweeting, Sam Querrey and Sergiy Stakhovsky.
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