Nadal wary of 'dangerous' giant-killer Tiafoe after Berdych rout

Rampant Rafael Nadal battered ex-world number four Tomas Berdych Sunday but said he would be taking a step into the unknown against "dangerous" Frances Tiafoe in the Australian Open quarter-finals.

The Spanish 17-time Grand Slam winner dismissed the unseeded Czech 6-0, 6-1, 7-6 (7/4) to tear into the last eight without dropping a tournament set.

Next in the firing line for Nadal is giant-killing American Tiafoe -- who celebrated his 21st birthday in style Sunday by beating 20th seed Grigor Dimitrov.

"It's going to be the first time that we play each other. Yeah, he's playing great," he said of 39th-ranked Tiafoe who created one of the shocks of the tournament by knocking out fifth seed Kevin Anderson in the first round.

"I know him, of course. He's been on the tour for a while. He's young. When you have younger players coming, they have always more attention."
"He goes to the net fast. He has a huge forehand, good serve. So let's see."
- Clock alarm -
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"I think it's already done. What can we do? It's all right. It's just a clock."
"I think the third set was the real Tomas Berdych," Nadal said after reaching his 11th Australian Open quarter-final. "He made more mistakes than usual in the first two sets."