Seven-time Grand Slam winner Mats Wilander believes that the reason Rafael Nadal has struggled to beat Roger Federer in recent times is because the Spaniard is trying to play too aggressively, which has led to mistakes.

Federer has played Nadal 38 times in what has been an intense rivalry over the years but only won on 15 of those occasions. However, the World No. 2 seems to have found the answer to the Nadal question and is currently on a five-match winning streak against the Spaniard.

The Swiss ace managed four wins in four meetings against Nadal in 2017, three of which came during the Australian Open, Miami Open and Shanghai Masters finals. The head-to-head record now stands at 23-15 to the 31-year-old.

However, despite the skewed head-to-head results, both players had a brilliant 2017 campaign, claiming all four Grand Slams by sharing two apiece. Federer has won seven titles last year, including the Australian Open and a record eighth Wimbledon title to overtake Pete Sampras' seven championship wins.

Nadal matched his conquests as well, winning six titles in the year, including the French Open and the US Open. The Spaniard, however, had the last laugh as he finished the year with the number one rank, sealing the spot after progressing into the quarter-finals of the Paris Masters.

However, with the 2018 season coming up and a host of other stars pulling out through injury, it is likely that Federer will again emerge as Nadal's biggest roadblock on the tennis court.

Wilander has urged the Spaniard to stop trying to play winners and play more like he used to in order to get the better of the Swiss ace.

"Federer wants Nadal to play aggressive and make mistakes," Wilander said, as quoted by the Express. "That's why he is rushing so much. That's part of his tactics and I think it's working. The last few times, Nadal was making too many mistakes trying to keep up with the pace of Roger Federer and I don't think he can do that.

"Nadal has to say, 'If you can beat me, beat me but I am not going to beat myself by trying to hit winners.' That's the only chance he has. He has a good chance if he does that and starts playing a little more like he used to, he has a really good chance of wearing Federer down mentally and physically."

Roger Federer and Rafael Nadal
Roger Federer and Rafael Nadal won a combined 13 titles in 2017 Getty