SHANGHAI — Roger Federer admitted that he came "very close" to defeat as he was given a huge scare before seeing off Daniil Medvedev 6-4, 4-6, 6-4 to open his Shanghai Masters defense Wednesday.

The 37-year-old Swiss top seed faces Spain's unseeded Roberto Bautista Agut Thursday in the last 16 after what was an unconvincing start against the Russian.

The 20-time Grand Slam champion initially wasted little time stamping his mark on the tournament, breaking the 22nd-ranked Medvedev in the first game.

But Medvedev, 22, fresh from winning the Japan Open, broke back and enjoyed even more luck on Federer's serve in the second set to force a third.

In what was the first meeting between the pair, Federer broke in the ninth game of the decider to finally destroy Medvedev's resolve in just under two nail-biting hours.

"In the third set I really started to figure it out," said Federer, who was roared on by a band of fanatical fans decked out in red tops.

"How aggressive or how tactical I wanted to make the match, and by trying everything, I found a solution at the end."

Federer, who was uncharacteristically flustered at times, said he was pleased with his performance, but admitted it had been a nervy one.

"Of course I feel pressure from the tournament organizers, the fans, my team, myself, because I know that sometimes coming through a tough first round can be the key to what's to come afterward," said the 2017 champion.

"Today was very close to maybe not getting that next step." — AFP