Facing double break point at 4-4 15/40 in the first set, Federer rallied to hold serve and win five consecutive games after breaking the Russian to close out the first set and again in the second game of the second set to race to a 3-0 lead.
Davydenko did break back to challenge Federer, but the five-time ATP World Tour Champion eventually sealed victory 6-4, 7-5 and will next play Marcos Baghdatis, who upset ATP World Tour No. 1 Rafael Nadal 6-4, 4-6, 6-4 in the feature night match.
Federer, who won the Cincinnati title in 2005, '07 and '09, has won 20 of 22 matches here since 2005. The Swiss is attempting to reach his second ATP World Tour Masters 1000 final in as many weeks, having fallen to Andy Murray last week in the Toronto title match. He is aso looking for his second title of the year and first since late January at the Australian Open.
"I know the danger [against Nikolay]... so it was a tough match for me. But I felt like I played really good considering I had not played well this week yet," said Federer, who had played just seven games en route to the quarter-finals. In his opener he was leading 5-2 when Denis Istomin retired with an ankle injury and in the third round Federer received a walkover from Philipp Kohlschreiber, who had a shoulder injury.
"Today I had a good ten minutes, and all of a sudden I'm up 6-4, 2-0. You don't know what happened, but you're in the lead. So it's just the way it goes. You got to make the best of it, and I'm happy and it's another successful year for me here in Cincy."
Date: 21.08.2010, Source: ATP