2015 Wimbledon: Roger Federer vs. Andy Murray is the sport's most underrated rivalry

While many have pegged Novak Djokovic for the finals given his historical dominance over Richard Gasquet, Friday's semifinal matchup between Roger Federer and Andy Murray isn't quite so cut-and-dry. The two have exchanged blows in their rivalry over the years, a rivalry that has spanned 23 matches in total. Despite this, most focus on Federer's matches against Rafael Nadal and Novak Djokovic.

But Federer and Murray play a similar game, and neither has a significant advantage over the other when it comes to executing those games. The most interesting thing about their rivalry to this point is how streaky its been for each player. You have Murray winning six of the first eight matches the two played against each other and then Federer winning four of the next six.

They started splitting matches after that point, with Federer ultimately trailing by two wins heading into last year. But Federer dominated Murray in 2014, winning all three of their matches to take a 12-11 lead in their head to head series. In their last meeting, Federer only dropped a single game to Murray.

Both have been excellent this tournament, though it hasn't been smooth sailing for either of them. Federer was pushed to four sets in just his third match of the tournament, but ultimately won out over Sam Groth. His next two matches were a breeze though, as he downed Roberto Bautista Agut in straight sets in the fourth round and No. 12 seed Gilles Simon in straight sets in the quarterfinals.

Murray was pushed to four sets against the hard-serving No. 23 seed, Ivo Karlovic. Their opening frame went to a tiebreak, and Karlovic took a 7-5 third set but Murray ultimately won it before it reached a fifth set. He then took down Vasek Pospisil, a surprise unseeded quarterfinalist, in straight sets.

The two have had a similar run through this year's tournament, and Murray is of the opinion that he's playing as well as he ever has, even up to par with his summer run in 2013, when he won Wimbledon to end Britain's 77-year drought of a men's singles champion. That was an incredible year for Murray, and getting a win over Federer in these semifinals before what many assume will be a showdown with Djokovic in the finals would be a great way to get this year up to par.

Both have been absent mistakes by and large this tournament, and Friday's match should come down to which one can force the other to make those mistakes. They're both hitting their winners, they're both avoiding unforced errors and on some point Friday, one of those things will have to give. Federer is obviously the best shotmaker in all of tennis, but Murray has shown in the past he can keep pace and has an answer to Federer's game.

Murray will need to be mentally strong, obviously. He's faded after early dominance on more than one occasion, and Federer is no stranger to big comebacks. Still, Federer would be best served to get out to an early lead and demoralize Murray from the onset. At this point, Federer has to be the favorite in the match. He's playing on his best surface, he's dominated Murray in recent outings and he's looked just a bit sharper throughout the tournament thus far.

Still, it's absolutely worth watching. You can catch the match on Centre Court following the Djokovic/Gasquet semifinal, which gets underway at 8 a.m.