Federer downs injured Isner for 101st career title

Holder Isner struggled to continue late in the second set, hampered by pain in his left foot.

He said afterwards that he was concerned that he may have broken bones.

Federer, who won his fourth Miami title, broke Isner three times in a blazing opening set.

But the American fought back in the second, levelling the set 3-3 and 4-4 before the pain made it difficult to continue.

Federer took the final two games for the victory.

"It was a dream start, relaxing my nerves," the Swiss said in a courtside interview.

But the American fought back in the second, leveling the set 3-3 and 4-4 before the pain made it difficult to continue.

Federer took the final two games for the victory.

"What a week it's been for me," said the Swiss. "I'm just so happy right now. It's unbelievable. I played here in 1999 for the first time and here I am in 2019. It means a lot to me."

Only American Jimmy Connors, with 109, has more career singles titles.

Even before the injury slowed Isner, Federer was the master, tempering Isner's big serves and winning 32 of 35 points on his own serve.