SUNDAY TIMES WEB DESK: Roger Federer admits he faces a real battle to land the 101st title of his career with the in-form Daniil Medvedev next up after Serbian Filip Krajinovic was dispatched 7-5 6-3 on Monday at the ATP and WTA Miami Open.

The Swiss superstar produced an excellent all-round performance despite being tested by the world number 103 who belied his lowly ranking by producing some excellent tennis during an exciting first set.

Federer, however, stylishly weathered the storm to seal the win – the 52nd of his career in Miami – and set up an intriguing last eight match with the highly-rated Medvedev.

The Russian, who is at a career high ranking of 15, saw off American Reilly Opelka 7-6 (7/5) 6-7 (5/7) 7-6 (7/0), and has won four ATP hard-court titles, including three since last August.

Federer beat him twice last year but is already a fan.

“He’s clever how he plays the court because he can play it up and down, and he’s unusual when he plays from back,” said the Swiss, who hit 14 aces and won an impressive 74% of points on his first serve.

“It’s a bit of a different approach.Thankfully I played him last year twice in Basel and Shanghai and I’m very impressed about his progress. I must say the last year has been unbelievable for him.”

Krajinovic struggled with injury last year as problems with his ankle, left foot and hand restricted him to just seven tournaments in the first seven months of 2018.

Yet some fierce hitting from the back of the court surprised the predictably pro-Federer crowd and a brilliant run and flick over the net handed him an early break for 3-2.

Keeping the pressure on, however, was a different matter as Federer broke straight back before pocketing the opening set.

The second set wasn’t as competitive, Federer easing home and finishing with 35 winners compared to the Serbian’s 18.