On Saturday, Roger Federer showed how dominant he still can be. A day later, he showed how vulnerable he still can be.

The 33-year-old Federer still managed to win his fourth title of the year, defeating unseeded Gilles Simon 7-6, 7-6 on Sunday to win the Shanghai Masters.

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Federer will move up to No. 2 in the world rankings today, surpassing Rafael Nadal. He trails only Novak Djokovic, whom he routed on Saturday in just more than an hour and a half, 6-4, 6-4.

"To win the biggest tournament in Asia is a treat," said Federer, who lost in the 2010 final to Briton Andy Murray, according to BBC Sport. "I got lucky to come through the first round after saving five match points. It's been a dream week."

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Federer won 24 of 35 points at the net, but he also finished with 36 unforced errors, compared to only 21 winners. Federer is one of four players, along with Djokovic, Nadal and Australian Open champion Stanislaus Wawrinka, to qualify for the season-ending ATP World Tour Finals in London in November. The top eight players qualify for the event.

"It makes me very happy winning here because this tournament means a lot to me," said Federer, as reported by atpworldtour.com. "I've always enjoyed coming here. I've come close a couple of times, but I've always wanted to win it as a Masters 1000.

"I feel unbelievable prestige to win this event. Especially putting my hands on the trophy for the first time is a good feeling, I must say. I'm very happy with the way I'm playing. Overall I'm just extremely happy right now."

Federer vowed that he would not have a letdown after dismantling Djokovic in the semis, but he did just that against Simon. Federer trailed 5-3 in the first set before rallying and was down 6-5, 40-15 to his French counterpart in the second set before Simon let him off the hook with a couple of unforced errors.

Federer's confidence likely was key in his win Sunday, which gave him his season-leading 61st win in his season-best ninth finals appearance.

Now the goal for the ATP World Tour Finals, and then in 2015 is to recover the consistence he had from 2004-07.

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