8 tournaments where Roger Federer has had the most missed opportunities

(5) Rogers Cup (Montreal/Toronto)

Alexander Zverev avenges his Halle final defeat with a win over Federer in the 2017 Rogers Cup final

At the sixth Masters 1000 event of the calendar, the Rogers Cup which alternates between Montreal and Toronto, two-time champion Federer has suffered two defeats apiece in the final in either city, making it four defeats in the tournament final.

Top seed and World No. 1 Federer triumphed in consecutive Toronto finals, beating Andy Roddick in 2004 and Richard Gasquet in 2006. In the final the following year in Montreal, the Swiss would squander a 6-5 40-0 advantage on serve in the first set en route to dropping the set in a tiebreak against Djokovic.

Federer would regroup in the second but would fall short in the deciding set tiebreak.

At a tournament which hasn't always been a regular feature in Federer's schedule over the years, the Swiss would reach a fourth Rogers Cup final in 2010, only to come up second best against Andy Murray.

Four years later, the Swiss would arrive at the title round, only to be thwarted by mercurial Frenchman Jo-Wilfried Tsonga.

In 2017, fresh off a record eighth Wimbledon title, Federer returned to the Rogers Cup, where a 16-match win streak came to an end against young German Alexander Zverev in the final. That meant the Swiss suffered a fourth straight reverse in the title round of the only Masters 1000 tournament in Canada.