Roger Federer admits his thrilling Indian Wells Masters final loss to Juan Martin del Potro will "sting", but not for long.

Federer wasted three match points before suffering a 6-4 6-7 (8-10) 7-6 (7-2) defeat to the Argentinian on Sunday.

The world number one served for a sixth Indian Wells title at 5-4 in the third set but Del Potro fought back before Federer played a poor tie-break.

Federer said the defeat would hurt, but he took plenty of positives from the tournament as his record slipped to 17-1 this year.

"I feel frustrated, you know, that I let an opportunity like this go by. Serving 40-15, any game I probably win – I don't know what the stat is – 90-something per cent,” he said, via the ATP World Tour.

"So it should sting, like you said, for a bit. The question is how long? It won't be long, but it's disappointing talking about a great match like this, losing, even though I was right there.

"Obviously there is not too much time to dwell over it. Like I said, I'm happy for Juan Martin.

"It's a tough one. And I still had a good week here. I still see the positives at the end of the day."

Federer said he enjoyed the battle against Del Potro, who won for just the seventh time in 25 clashes between the pair.

"It was a great match, honestly. Good fun. Good intensity. We enjoy that. And also it was tough and fair on the court. It was Juan Martin and myself," he said.

"At the end you saw we are appreciative of the finals that we played against each other, which I think is really important for both of us."