Roger Federer has edged into the quarter-finals of the BNP Paribas Open with a three-set victory over fellow Swiss Stanislas Wawrinka.
The second seed and defending champion had the chance to serve out the match at 6-3 5-4, but he was broken before losing the tie-break 7-4.
Wawrinka, who has now beaten Federer once in 14 matches, moved into a 3-1 lead in the third, only for the 17-time Grand Slam champion to break back twice and seal the victory 7-5.
The 31-year-old could meet Rafael Nadal in the last eight if the Spaniard beats Ernests Gulbis.
It would be the first meeting between the pair since Federer defeated Nadal in the semi-finals of last year's competition on his way to winning the title.
