A day after racing to victory in 47 minutes, five-time champion Roger Federer was stretched by Denis Istomin 3-6, 6-3, 6-3 in the second round of the Swiss Indoors yesterday.

Federer, the top seed at this ATP World Tour 500 event, fired off six aces and broke his Uzbekistani opponent two times to secure the victory in one hour and 48 minutes.

“I thought I was lacking rhythm in the first set,” said Federer. “Istomin played well. It was one of those sets that was tough to lose but the important thing was to bounce back in the second set and get my teeth into the match.”

The Swiss is playing in his first tournament since the Shanghai Rolex Masters two weeks ago, when he won his maiden crown and rose to No. 2 in the world for the first time since May 6, 2013. The last 33-year-old to be ranked No. 2 was Andre Agassi on September 1, 2003.

Federer continues his quest for a sixth crown in Basel against fifth seed Grigor Dimitrov in the quarter-finals.

“I’ll recover in time for my next match,” said Federer. “In recent times I’ve played in so many matches that I know how to bounce back.” Federer won the Basel title in 2006, 2007, 2008, 2010 and 2011. He finished runner-up to Juan Martin del Potro in the past two years.