Roger Federer's movement appeared somewhat restricted towards the end of his Rogers Cup final defeat to Alexander Zverev, but the 19-time grand slam champion reported nothing more than "aches and pains here and there" after the match.

While Zverev played superbly in Montreal on Sunday to triumph 6-3 6-4 and secure his second Masters 1000 title, there were concerns over the fitness of Federer when the 36-year-old seemed to struggle physically at the end of the second set - amid suggestions of a back problem.

With the US Open just two weeks away, any injury would come as a significant blow to the Swiss, who has already won the Australian Open and Wimbledon in a stunning 2017 season.

Federer did not appear too concerned by his condition, however, after suffering a first loss in 17 matches.

He was quoted by the ATP World Tour's official website as saying: "I felt all right all week. I had a bit of muscle pain, aches and pains here and there, just because it's back on the match courts, on the hard courts.

"After vacation and practice, it's always a bit of a shock for the body. We'll have to wait and see now how I feel in the next couple of days."

Federer was able to remain upbeat, despite losing a final for the first time this year.

"It is a positive week in the end," he added. "The final was unexpected. But it's keeping up with the good results of this year.

"Of course, I'm disappointed with today. I thought I would do better. I wanted to fight a bit more and make the match a bit more tighter. I had opportunities. But Zverev played extremely well. He played well all week."

At the age of 20, Zverev is already firmly established as the brightest young star in tennis.

"I'm just really happy for him, to see that he's taking everything not just to the next level, but the two next levels, winning two Masters 1000s," said Federer.

"It's extremely difficult to win. He's won two this year. It's a wonderful achievement for him. I wish him the best for the coming months and hope he can finish the season very strong because there's opportunities now."