It's all good for Roger Federer heading into ATP Tour semifinals

So this edition of the ATP World Tour Finals was supposed to be remembered as the moment when all those predictions of a changing of the guard came to pass, eh?

Not so fast, bub.

True, five of the nine players (we're including Pablo Carreno Busta, who stepped in to replace injured Rafael Nadal) were World Tour Finals newbies. Six of the nine were 26 years old or younger. Grigor Dimitrov, a semifinalist in London, has patiently borne the nickname "Baby Fed" since he was a teenager, waiting for this moment to come.

Plus, the draw this year is strikingly devoid of seasoned warriors, including Tomas Berdych, Jo-Wilfried Tsonga, David Ferrer and Richard Gasquet -- all of whom had played in at least two year-end events. None of them qualified, and all are in their 30s.

But let's pause for a reality check. Roger Federer. Make that "the 36-year-old Roger Federer." He is the last man standing among the old guard at these championships, and odds are he'll also be the last guy standing tall at the trophy presentation come Sunday. A semifinalist at the World Tour Finals for the 14th time, Federer will have to get by David Goffin first (which you can watch here Saturday at 9 a.m. ET.)

Federer has been conducting a master class at this event. Being the lone representative of the Big Four, plus Stan Wawrinka, he's acting less like he's carrying the weight of the world on his shoulders than dancing with all these would-be stars, practicing all his moves.

But if there is a slight concern for Federer heading into Saturday's semis, it's this: He tried to stretch, pull and yank 20-year-old wunderkind Alexander Zverev around the court. Although it ultimately worked out, Federer relied too heavily on his slice backhand and other dinky stuff.

Leading 5-1 in the third set of that match and in a foul mood, he suddenly had a conversation with himself. "I'm one game away from qualifying for the semis," Roger said to the media afterward. "You want to get upset?"

He went on to explain: "There's zero reason for that [negativity]. I think it's important sometimes to remind yourself that it's all good."

It was "all good" for Federer in his next match, as well. Having already clinched the top seed in his group, he dropped a first-set tiebreaker to Marin Cilic, then raged back to win. It was a mere matter of overcompensation. This time, instead of being too coy with his shot selection, Federer described his early play as "overaggressive."

No problem. He recalibrated and won going away.

For Goffin and the other semifinalists, Dimitrov and Jack Sock (whom the Swiss beat in the opening match in London this past Sunday), Federer has proved again that he has more staying power than the Rolling Stones. It was one thing to pull off that stunning win at the Australian Open in January -- with a five-set comeback against Nadal, no less. It's quite another, at his age, to have kept up his spectacular form -- and jolly, "It's all good" attitude over the course of the entire year. What a gorgeous bookend a World Tour Finals title would make to his 2017 season.

Federer has won 19 Grand Slam singles titles. He won't be playing anyone this weekend who's even been as far as a major final. The most convincing player left is Dimitrov, who had qualified for the semis midweek by winning his first two matches.

Dimitrov, 26, is considered by many to be a case of arrested development. But that can be said for an entire generation that has faced monumental difficulties pushing the elders out of its way. It isn't the guard that's changing, just the scenery. But there's still one landmark that stands out like the towering feature of the landscape.

It's all good for Roger Federer. For the younger players, not so much.