How long can Federer defy gravity?

Chicago

DAY was breaking in the California desert, and Roger Federer was yawning on the tarmac.

How much sleep?

"Five hours," he said. "Not enough after a match like that." The final of the BNP Paribas Open had indeed been quite a test: a 2h 42min duel with Juan Martín del Potro that was out of tune with Federer's crescendo season. He ended up losing in a lopsided third-set tiebreaker after serving for the title and holding three match points at 5-4 in the final set.

"It's always disappointing when you lose having had match points," Federer said. "I think I was a bit lucky to even get into a third set, and he was a bit lucky to get to the tie-break and finish it off. Sadly, I lost my game a bit at the end."

But that was Sunday afternoon. This was Monday morning, and Federer was back on the move: arriving at sunrise at the Jacqueline Cochran Regional Airport in Thermal, California, a short drive from Indian Wells.

Along for the ride were his agent Tony Godsick and agent Alessandro Sant'Albano, and Federer's coach Severin Luethi.

Federer's wife Mirka, and their four children were set to travel separately to Florida for the Miami Open. But Federer was breaking away for a few hours, catching a private jet to Chicago to promote the Laver Cup, the team event that he helped create with Godsick and played at last year in Prague.

This was a long-planned detour, but it also ended up serving as a way to quickly change the chip after the final in Indian Wells, Federer's first loss in 2018.

"Roger's life, if it's not hectic, it's not Roger's life, because it's all he knows," Godsick said.

Federer, back at No 1 at age 36, is clearly pushing himself to make it happen after back-to-back three-set matches on Saturday and Sunday.

"It's passion and a love for the game," he said. "And Laver Cup is something that is very dear to me, so clearly I always have extra energy for the Laver Cup. For my own career, I don't play as much anymore, and when I am there, it's all out and full speed, and then I need the time away again."

As the plane approached Midway International Airport after about three hours in the air, Federer warmed up for chilly Chicago with a quick quiz.

NFL team? "Bears," he answered.

NHL team? "Blackhawks." Baseball team? "Cubs." And? "White Sox," he said triumphantly after a pause.

There was no need to test him on the NBA. Federer has been an NBA fan since boyhood and was 16 when Michael Jordan and Scottie Pippen won their last title with the Bulls in 1998.

A visit to United Center, the home arena of the Bulls and the Blackhawks and the site of the Laver Cup in September, was a big part of Monday's dense itinerary, which was focused on building interest for the event and creating social-media content.

Federer walked down the plane's stairway shortly after 1pm Chicago time and was soon at a deep-dish pizza parlour downtown for a photo op with the 79-year-old Rod Laver, John McEnroe and the Australian star Nick Kyrgios.

A former No 1 player, McEnroe still wears many a tennis hat and is the captain of the Laver Cup's Team World, which lost to Federer, Rafael Nadal and Team Europe in last year's inaugural edition. Kyrgios, 22, was one of the most enthusiastic members of McEnroe's team in Prague, leading the cheers and nearly defeating Federer in the final and decisive match of the competition.

"The funnest week of my career so far, better than the Grand Slams," said Kyrgios, who for all his evident talent has yet to get past the quarter-finals of a Grand Slam tournament.

If he comes closer to fulfilling his massive potential, he and his generation will be critical to the Laver Cup's uncertain future.

After proving Laver Cup could be done, Godsick and Federer now must prove it can be sustained, both economically and competitively, in a sport with a full calendar. Any new event that lacks ranking points and mandatory participation is vulnerable to irrelevance.

The Laver Cup's epicness will be determined in large part by who actually decides to play. The competition comes less than two weeks after the US Open. Might some European and Asian stars - some of whom, like Hyeon Chung of South Korea, are represented by IMG - choose to save their energy for other late-season events?

"I think that's going to always be an open question a little bit," Federer said. "I hope it's not going to happen. I hope by showcasing and giving them such an amazing platform and being part of something quite unique, being on a team together, that they would not want to miss it. There comes a bit of sacrifice with doing something like this."

Federer continues to fly improbably high as the oldest No 1 in ATP history. How long can he defy gravity?

"When I started with him, I made many more predictions than I do now, and I was very often wrong," Luethi said. "I am ready to be surprised by him. I'm actually expecting to be surprised by him, and I think the best thing is to leave it open and not try to put fences around it."

For Federer, who will most likely skip the clay-court season for a second straight year, the key is internal at this stage.

"When you go to, say, Rotterdam, you need to go there with fire," he said. "If you're not excited at this age, don't do it. It's that simple." NYTIMES