MASON, Ohio - Novak Djokovic had to rally against a lowly qualifier to get another shot at a title he's never won. Next in his way: Roger Federer, who has more Cincinnati trophies than anyone else.

Djokovic got a little help in the tiebreaker and pulled away to a 4-6, 7-6 (5), 6-2 victory over Alexandr Dolgopolov on Saturday to reach the Western & Southern Open final.

He'll face Federer, a six-time champion who has never lost a Cincinnati title match.

"There's always a lot at stake, this one in particular," Federer said.

The top-ranked Djokovic is 0-4 career in finals at Cincinnati, where he's never even won a set. It's the only one of the nine ATP Masters to elude him.

A victory Sunday would make him the first player to win all nine ATP Masters during his career.

"I gave myself another chance to fight for the trophy," Djokovic said. "That was the goal and that was the wish coming here in Cincinnati. Obviously last couple of years, it was always in the back of my mind, the potential history making, and obviously that motivates me even more.

"Having that in back of my mind helped me to go through matches like the one today."

On the women's side, defending champion Serena Williams gave herself a chance to make it two Cincinnati titles in a row. She beat 14th-seeded Elina Svitolina 6-4, 6-3.

Williams will face third-seeded Simona Halep, who beat Jelena Jankovic 6-1, 6-2 in the other semifinal. Halep's win will move her ahead of Maria Sharapova, who withdrew from Cincinnati with a leg injury, into the No. 2 seed for the U.S. Open.

"It definitely feels good to be back in the finals," Williams said. "I was playing aggressive more today and it really helped me, and it can keep me going for the next few weeks."

Federer won the marquee matchup of the semifinals, using his steady serve to beat Andy Murray 6-4, 7-6 (6). The defending champion is trying for an unprecedented seventh title in Cincinnati.

It's his first tournament since he beat Murray in straight sets at Wimbledon before losing to Djokovic in the finals. And he's looking very fresh, especially with his serve.

He hasn't been broken during his four matches, a total of 29 service games. He lost only 14 points off his serve while beating Murray for the fifth time in a row.

"I've definitely been holding my serve very well," Federer said. "If you seldom get broken or you don't get broken in a match, it's quite hard to lose at this point."

Murray played a lot of long, draining matches during the last week. Mainly, he couldn't keep up with Federer's serve.

"Today it was a tough one," Murray said. "I started slowly the last couple of days. Almost got myself back in the match today, and I just didn't return as well as I would have liked. That was the difference."

For a while, it looked like Djokovic was going to come up short of his finals destination again. He needed a few mistakes by the 66th-ranked Ukranian to help him pull it out.

Dolgopolov took advantage of Djokovic's sluggish start and won the first set in 31 minutes. It wasn't the first time that Djokovic has fallen behind to him: Dolgopolov got up 7-6, 4-1 at Miami earlier this season before losing in three sets.

Djokovic took a medical timeout after the fifth game of the second set. A trainer checked his lower rib cage on his left side and his abdomen — Djokovic called it a "minor problem." He went back out on court and took it to a tiebreaker.

Up 5-4 and serving, Dolgopolov dumped a pair of backhand shots into the net. Djokovic closed out the 67-minute set with a forehand winner.

"He just makes you play, and (he) plays more careful on the big points," Dolgopolov said. "You have to beat him and go for the risk.

"Ifs, a lot of ifs. You make a decision and you have to roll on it."

Dolgopolov committed 20 unforced errors as the third set slipped away.

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