NORCROSS, Ga. (AP)—John Isner, in position to win back-to-back tournaments for the first time in his career, is savoring the confidence that has come with his success.

Isner overwhelmed Gilles Muller in the third set to win 7-5, 6-7 (3), 6-1 on Saturday to reach the Atlanta Tennis Championships final for the second straight year.

Isner, the No. 3 seed, will face top seed Mardy Fish in Sunday’s final. Fish beat Ryan Harrison 6-2, 6-4.

Fish, No. 9 in the world, beat Isner in the 2010 Atlanta final and has not lost a set this week. Isner can improve his No. 35 ranking by beating Fish.

Coming off a victory in the Hall of Fame Tennis Championships on the grass courts in Newport, R.I., two weeks ago, Isner said his game is soaring with his confidence on Atlanta’s hard courts.

“I’ve been waiting for this feeling for about four or five months,” Isner said. “Now that I’ve got it, I don’t want to let it go.”

Isner’s attempt for back-to-back wins resembles Fish’s climb last year. Fish had never won two straight tournaments before winning in Newport and Atlanta.

“I came in on a roll,” Fish said. “I had never won two tournaments in a row last year. I felt like I was a different player than in years past and had yet to prove it. That was sort of the start of my run to the top 10.”

The 6-foot-9 Isner, who is best known for his powerful serves, said he is making good decisions that help him enjoy a more complete game.

“It’s as simple as confidence,” he said. “I always play my best when I’m confident. I move my best when I’m confident.

“I’m not the fastest guy out there but I feel I’ve been moving well this week and that comes with having a clear mind and making the right decisions on the court.”

In the key game of the match, the 6-foot-9 Isner hit an overhand winner to break Muller’s serve for a 2-0 lead in the third set. Muller reacted by slamming his racket to the court, demolishing the racket.

Muller never recovered. Isner broke the left-hander’s serve again for a 4-0 lead.

“I thought I made a lot of hard work in the second set to win that set and then right away in the beginning of the third one, I threw all my chances away,” Muller said. “It was hard to take.”

Isner said he hit “kind of a junk volley” to set up the key overhand winner.

“It took some pressure off, for sure,” Isner said.

Isner hit 28 aces, including 11 in the third set. Muller had 16 aces, but only three in the final set. Muller never broke Isner’s serve.

It was the second straight year Isner, the former University of Georgia star, beat Muller, from Luxembourg, in three sets in Atlanta.

Harrison, 19, was the first American teen to play in an ATP Tour semifinal since Sam Querrey lost to Russia’s Dmitry Tursunov in July, 2007 in Indianapolis.

“It’s disappointing to go out, but it’s obviously the first of hopefully many semifinals that I’ll have,” Harrison said.

By playing in the semifinal, Harrison will become the first American teen since Querrey to be ranked in the top 100. Harrison from Shreveport, La., began the tournament at No. 120.

Australia’s Bernard Torric, who is 18 and ranked 73rd, is the only other teen in the top 100.

“Some of the dreams I have are obviously to reach the top 10 and move up to No. 1 if I can,” Harrison said. “That never happens unless you reach the top 100 first, so that’s a big milestone to accomplish. It’s going to be exciting to see my name there next week.”