Have you ever wondered how much better Roger Federer could have been if Rafael Nadal never existed?
The 16-time Grand Slam winner has pretty much achieved everything possible in tennis, apart from winning a Davis Cup trophy for Switzerland and an Olympic Gold medal on his own.
But his resume is long and one that is extremely difficult to match.
He already has four Australian Open trophies, six Wimbledon titles, is a five-time champion at Flushing Meadows and has a sole French Open success to his name and you wouldn't bet against him adding more to this list even though he now sits on wrong side of 30.
Some say he has already done enough to be called the best player of all time, but that is a debate for another time.
The 30-year-old made it through to the semi-finals of the Australian Open for the ninth straight time on Tuesday, but standing in his way in the final four was long time nemesis Nadal.
Their semi-final match-up at Melbourne Park was the first time in seven years the duo had met before the final at a major, but it was the same old result for Federer.
Nadal didn't panic when he dropped the first set and eventually overpowered Federer 6-7 (5-7) 6-2 7-6 (7-5) 6-4 in a manner he has done on so many occasions over the past decade.
The victory was Nadal's 18th overall against Federer from 27 matches, with the Spaniard also holding an impressive 8-2 head-to-head record over his arch rival in Grand Slam encounters.
Of those 10 match-ups in majors, all have been in finals apart from their clash at Melbourne Park this year and their first ever meeting in a Grand Slam way back in 2005 on the dusty red clay at Roland Garros.
And the only time Federer has been successful against Nadal at one of the four Grand Slams has been on his preferred surface of grass at Wimbledon in 2006 and 2007.
Federer says he is aware of his poor head-to-head record against Nadal, but believes it is not important.
"At the end I care about my titles, if I'm happy or not as a person," Federer said.
"Head-to-heads for me are not the most important."
Titles are more important than head-to-head records, but it's easier to win titles with a better head-to-head record against the top players.
"I always think he (Nadal) plays a bit better against me than against other players," Federer added.
"I don't know if it's true, it's my assumption."
"I feel he plays really good against me."
"I think he has a clear plan and he follows that one very well."
Federer has now made just one final in his past eight Grand Slam appearances, but that is probably more due to his age catching up with him and the emergence of Novak Djokovic.
You should never write off a champion and I certainly won't be doing that with Federer, but you have to wonder if his already exemplary record could have been even better if not for a man named Nadal.