8 tournaments where Roger Federer has had the most missed opportunities

(6) ATP Finals

Nalbandian claws back a two set deficit to stop Federer in the 2005 ATP Finals title match in Shanghai

Record six-time champion Federer has endured four final defeats at the season ending ATP finals (once at Shanghai 2005 and thrice in London -2012,14-15).

Two-time defending champion Federer arrived in the final of the 2005 ATP Finals in Shanghai, one win away from tying John McEnroe's stunning 1984 win-loss mark of 82-3 and a share of the best win% in a season (96.5).

It had been a magnificent season for the Swiss as he raked up 81 match wins, 11 titles and lost only three times during the season, squandering match points in the Australian Open semifinal against Marat Safin and in the Monte Carlo quarterfinals to French teenager Gasquet before coming up short in a first French Open semifinal against Nadal.

Federer sailed unbeaten through the round robin stage of the ATP finals and faced up against old foe Nalbandian in the final. Two tiebreaks later the Swiss was a set away from tying McEnroe's best start to a season, but Nalbandian would have other ideas.

The Swiss would be denied a third straight ATP Finals title and a share of the best start to a ATP season as Nalbandian triumphed in a deciding set tiebreak.

As the year end tournament moved to London, Federer won consecutive titles (2010-11) but would fall short in his second attempt at a three peat following a straight set defeat to Djokovic.

Federer would come up second best in the title match of the ATP finals on two further occasions, both times against Djokovic, withdrawing before the 2014 final owing to a back injury and losing in straight sets in the 2015 final.