And while we're at it, add Andy Murray to the mix, too.
Now, to be fair, the Fed-Ex bandwagon, which is as crowded as ever, is a completely understandable ride to take at the moment.
The rise back to the top started with his Wimbledon performance, which was vintage Federer.
In the semifinals, Federer was broken just once against Djokovic, who was No. 1 in the world at the time. In the finals, it was more domination from Federer, as he put away home favorite Andy Murray, who was playing arguably the best tennis of his life at the time.
Murray did, of course, go on to get revenge in the Olympics, but it's safe to put more worth in Wimbledon simply because it is a true major.
Federer's momentum reached new heights two weeks later at the Western & Southern Open in Cincinnati.
After strolling through the competition, Federer once again found himself matched up with Djokovic, but the highly anticipated battle was anything but competitive. Fed-Ex threw a bagel on Djoker in the first set and held serve in the second en route to a tiebreak win.
He lost six games. In the final. Against Novak Djokovic. On a hard court. Let me just put it this way: A healthy Federer is a scary Federer, no matter how old and grey his critics might make him sound.
And just like that, with Rafael Nadal still out due to a knee injury, Roger Federer's deafening return to the No. 1 spot has him as the clear favorite in New York.
Not so fast.
Despite his awful performance in Cincinnati, I'm still not convinced Novak Djokovic isn't the best hard-court player in the world. Of the last three hard-court majors, Djoker has won them all. It's not like Federer hasn't been close during that span, but the Serb has established himself as the clear king.
So what happened last week?
You have to chalk up his first set against Federer as more of a fluke than anything. He was playing in his third tournament in as many weeks and looked both physically and mentally exhausted.
As a result, he never really woke up until the second set, which turned out to be a hard-fought battle where neither player was broken.
Should Federer and Djokovic battle it out under the bright lights of New York on what would be a much bigger stage, expect more tiebreakers, less bagels and less naps from Djoker.
Oh, and by the way, there's also Andy Murray, who beat both men in the Olympics and should have plenty of rest after departing early in his last two tournaments. Regardless of those results, the Brit is playing top-notch tennis and should have no problem replacing Nadal in the Big Three later this month.
So, while Federer has looked like Superman during the past few months, don't be so quick to crown him the champion of the United States just yet. In fact, this might just be the most wide open major of the year.