Atlanta, July 22 (IANS) Former World No.1 Andy Roddick ousted top seed and compatriot John Isner 6-4, 6-7(5), 6-4 to enter the final of the Atlanta Open.

Though the two-time defending finalist Isner cracked 26 aces, Roddick was more effective on serve, winning 78 percent of his service points to Isner's 71 percent.

In the final set, after missing out on four break point opportunities when leading 4-3, Roddick capitalised in his next return game. He converted his second match point to clinch the victory in two hours and 28 minutes Saturday evening.

With the win, Roddick defeated Isner for the fourth time in six meetings and will now be facing Gilles Muller of Luxembourg. The World No. 63 reached his first tour-level final since 2005, beating number eight seed Go Soeda of Japan 6-4, 6-3.

Muller is aiming to lift his first ATP World Tour trophy and earn 250 points, having finished runner-up twice in 2004 at Washington DC (lost to Hewitt) and 2005 at Los Angeles (lost to Agassi).