Roger Federer's age-defying revival can be in part attributed to the downfall of Novak Djokovic and world number one Andy Murray, according to Janko Tipsarevic. The Swiss has won the three biggest titles of the season so far, adding an 18<sup>th grand slam title at the Australian Open, before winning the Masters 1000 crowns at Indian Wells and Miami.

The 35-year-old – now the new world number four – will take a break from the sport until the French Open in May, missing the crux of the clay court season in an effort to manage his workload. While Federer and Rafael Nadal has staged a barely believable re-emergence in the men's game, the fortunes of 'big four' rivals Djokovic and Murray have been on the opposite incline.

Since contesting an entertaining final at the Qatar Open, which Djokovic won in three sets in Doha, both players have struggled to recapture their form from 2016. Murray remains world number one but his victory in Dubai in February is a rare success during a campaign that saw him lose in the last 16 in Melbourne, knocked out of Indian Wells in the second round and withdraw from the Miami Masters with an ongoing elbow injury.

Djokovic endured a hapless end to last season and that run has continued, having been dumped out at the second round in the first major of the season. Defeats to Nick Kyrgios in Acapulco and Indian Wells followed before, like Murray, he withdrew from the event in Miami.

Roger Federer and Novak Djokovic
Federer has re-asserted himself as a player to beat after years of Djokovic dominance. Getty Images

And fellow Serbian Tipsarevic believes Djokovic and Murray's shortcomings have led to Federer's outstanding success in 2017. "Federer is a great champion, but one of the reasons he is in a position he is today is because Murray and Djokovic are not playing at their best level," he told Sport Klub.

"I am not sure that Federer would stand a chance playing Novak from last year – I am not saying this because Nole is my friend, but because that is what I really think. Secondly, I was told that this year was the fastest Australian Open ever, it was the first year in who knows how many that the courts weren't resurfaced. If the court isn't resurfaced, it gets faster every year. Also, the balls in Melbourne usually get bigger as the match progresses and this year they were getting smaller.

"Federer wanted to prove in Melbourne that he is not done, he has beaten Kei [Nishikori] in five, [Stan] Wawrinka in five and Nadal in five. I think that before he used to play with some niggles and that now he is pain-free. Besides, I think Ivan Ljubicic helped him improve his backhand, Roger is hitting the best backhands in his career."