When Roger Federer landed heavily on his knee on his beloved Wimbledon turf 12 months ago, few would have put money on the popular Swiss walking back through the All England Club gates as the favourite to win a 19th grand slam title.

Yet that is the reality facing 84th-ranked Alexandr Dolgopolov when the Ukrainian faces one of Wimbledon's all-time favourite sons in Tuesday's first round match on Centre Court.

Things could not have been more different last July.

That painful tumble in Federer's semi-final defeat by Milos Raonic sparked a chain of events that many feared would end the Swiss great's storied career.

Just days later, he put a full stop to his 2016 season, saying he needed time to receive "more extensive rehabilitation" on his stricken knee which had required surgery months earlier.

But the man who is a month shy of his 36th birthday has been rejuvenated by the enforced six-month break.

After capturing a record 18th grand slam trophy at the Australian Open in January, he is once again proving to be a formidable force -- winning back-to-back titles at Indian Wells and Miami for the first time since 2006.

While he shunned the entire claycourt season to give himself "the best chance for Wimbledon", a ninth title at the Halle grasscourt tournament has put him in the zone for Wimbledon.

"I don't want to be at the mercy of my opponent. I want to take charge, play aggressive myself," Federer, seeking his first title here since 2012, told reporters.

"So for that I need to be fast on my feet and quick in my mind. I just need enough rest so I can play enough inspired tennis."

Considering Dolgopolov has not taken a set off Federer in three meetings, the chances are he will be cannon fodder for the Swiss as Federer begins the pursuit of a record eighth Wimbledon title and a record 85th match win at the grass court major.