World number two Roger Federer has admitted that he was fortunate to beat Stanislas Wawrinka in their fourth-round clash at the BNP Paribas Open.
The Swiss was taken to three sets by his compatriot on the main court, but eventually won through 6-3 6-7(4) 7-5 in two hours and 20 minutes.
"I definitely got a bit lucky out here tonight," Federer told reporters.
"Stan's an amazing player and a good friend - I'm happy to get through."
Federer will now face Rafael Nadal in the quarter-finals at Indian Wells.
