World number three Roger Federer swept aside Juan Martin del Potro in an hour and a half to win the World Tennis Tournament in Rotterdam.

The Swiss repeated last month's Australian Open quarter-final win over Del Potro with a 6-1 6-4 victory.

Federer, 30, stormed into a 5-0 lead as he dominated the opening set.

And he got the crucial break in the second when he brought the Argentine to the net before firing a forehand past him to break for 3-2.

Federer's second Rotterdam title, and his 71st on the ATP Tour, takes his head-to-head record against Del Potro to 9-2.

It also maintains the 16-time Grand Slam champion's fine indoor form from 2011, which he ended with wins in Basel, Paris and London.

"Even if I had a good indoor season last year, this is a great start," he said. "It's incredible that it took me seven years to come back and defend my title, I hope the next time is not so long. But if it is, then it means I'll be playing for another seven years."

Federer has now assured himself of a 12th consecutive year in which he has won at least one ATP title.

Del Potro admitted: "He played much better than me today. I didn't take the break points when I had them.

"It's really difficult to beat Federer if you have the chances and don't take them. He was more confident and concentrated than me in the important moments and I think that was the key."

Source;bbc