World number one Roger Federer [Images] battled back from a break down in the final set to fend off a rejuvenated Lleyton Hewitt [Images] 6-3, 6-7, 7-6 on Saturday to reach the final of the Cincinnati Masters.

Australian Hewitt saved three match points, including one in the second-set tiebreak, but Federer roared back from 3-2 down in the third set to set up a clash with American ninth seed James Blake, who beat fifth seed Nikolay Davydenko of Russia [Images] 6-4, 6-2.

"I think it was the best match I've played this week, no doubt," Federer, who is now one win away from bagging his 50th singles title, told reporters.

"I think he played well, too. In the end I've got to be happy I came through. It's nice to win a third-set tiebreak after losing one last week (to Novak Djokovic in the final in Montreal)."

Federer had won the last 10 meetings between the two and despite a misfiring forehand in the early stages, the Swiss looked on course for a straightforward win when he eased through the first set.

But Hewitt, appearing in his fourth semi-final of the year, battled back brilliantly, retrieving everything and returning the Federer serve with interest.

The Swiss stepped it up in the second set, losing just five points on his serve as they headed into a tiebreak, though Hewitt had to save a break point in the third and 11th games.

Hewitt then raced to a 5-2 lead in the tiebreak but Federer hit back and forced a match point at 6-5 only for the Australian to save it with a deft drop volley. 

"SEVEN LIVES"

Riding the momentum, the former world number one, who is set to rise from 20 to 16 in the rankings after this week, clinched the tiebreak 9-7 and then broke Federer to lead 3-2 in the third set.

The Swiss broke straight back and then missed four chances to break in the eighth game and two games later, Hewitt saved two more match points.

In the tiebreak, though, a couple of loose errors put Federer in charge and he cruised through it 7-1 to take his place in the final.

"The baseline rallies weren't going the way I liked," he said. "He was just being steady and eventually I would miss or he would play a little bit more aggressive and I would be in trouble.

"I should have won earlier after having 15-40 a couple of times but it needed a tiebreak because he hangs in there. He's like a cat, with seven lives. How many do they have? Nine, yeah, thought so, seven would have been easy."

A rejuvenated Hewitt said there had been little between the two.

"It could have gone either way, there were only a couple of points in it," Hewitt said.

Blake went into his match with Davydenko having won all of their five previous meetings but the Russian jumped out to a 2-0 lead.

Blake then reeled-off four straight games, Davydenko broke back and levelled at 4-4 before the American broke again in the 10th game to take the set.

Blake then romped through the second set to set up a clash with Federer, who has beaten him in all six of their previous matches.

"He (Davydenko) is someone I feel like if I play my best I can dictate and take it to him," Blake said.

"Roger has clearly been the best player in the world for the last few days, but when I get into a final I know I'm playing great tennis, so I have a chance."

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