The problem with being an all-time great is that you're judged harder than everyone else.
Roger Federer is 38, no. 3 in the world and made a final, semi-final and quarter-final at three of the four grand slams in 2019. He finished the grand slam season with an 18-4 win-loss record across the Australian Open (fourth round), French Open (semi-final), Wimbledon (final) and US Open (quarter-final).
The Swiss maestro also added three ATP victories in Dubai, Miami and Halle to take his enviable career titles tally to 102.
Many of Federer's much younger rivals can only dream of such a season. Some will play for years hoping for one to hang their hat on. But Federer's sustained excellence means every stumble is scrutinised more than his peers and each loss raises the inevitable questions: "Is he past his best and when will he retire?".
The former world no. 1, widely regarded as the best of all time, might not win another major. He might have to be content with 20 and watch as his two biggest rivals, Spaniard Rafael Nadal (19) and Serbian Novak Djokovic (16), surpass him.
We don't know when Federer will bow out of world tennis and similarly whether it will be as a winner or after a defeat. Either way, nothing should detract from what he's given the sport. Federer transcends tennis. You might not be a tennis fan, but you're on the Fed Express.
His graceful game style and jaw-dropping shot making draws people in as does his gracious-in-defeat attitude and knowledge and respect for the sport's history.
He's never retired from a match, a remarkable feat given the amount of tournaments he's played. Against Grigor Dimitrov in the US Open quarter-final last week Federer had back and neck pain. He took a medical time out but kept playing, eventually bowing out in five sets.
Post-game, he looked dejected but was wary of taking the spotlight from Dimitrov.
"This is Grigor's moment and not my body's moment, so ... it's OK," Federer said. "I thought he was tough off the baseline. He mixed up well, which gave me all sorts of problems with the rhythm."
Federer's next grand slam chance will come in January at the Australian Open.
A student of the game, he relishes playing on a court named after one of his own heroes, Rod Laver. Like Laver, Federer will go down in history.
We can only hope the next tennis superstar learns from Federer and embodies the traits which make him universally respected.
Justine McCullagh-Beasy is an ACM journalist