Roger Federer's record 16th semifinal appearance at the ATP Finals came to an end with a straight-sets loss to Stefanos Tsitsipas.

The 38-year-old Swiss will square against Alexander Zverev in a South American tour later this month.

More: Tsitsipas Sweeps Federer, Into ATP Finals Title Match

Federer said he's "extremely excited" for 2020 and cited a four-point plan he hopes to follow for success:

*Sustain the level of play he showed winning the 2019 Miami Open and reaching the Wimbledon final.

*Stay healthy

*Maintain a healthy balance between family and professional life

*Attack opportunities.

"I've got to keep on playing at the level like I have this year, and then I will create some chances," Federer told the media in London after his 6-3, 6-4 loss to Tsitsipas. "I thought I played some consistent, solid tennis.

"Got to take care of my body, listen to the signs, work well with the team, get the balance right with everything that's happening in my life."

The 20-time Grand Slam champion pointed to miss opportunities as an area he must address. Federer failed to convert two championship points against Novak Djokovic in losing a gut-wrenching Wimbledon final, did not convert any of the 12 break points he had bowing to Tsitsipas in the Australian Open fourth around and cashed in on just one of 12 break points he had in today's loss.

Federer said he's aiming to excel at crunch time.

"Then when the matches come, you know, it's not maybe as easy as it was maybe 10, 15 years ago where you're just going to play very good day in, day out, maybe you need to do extra effort sometimes for that to happen," Federer said. "Maybe that's what it felt like today is just things were complicated, you know, but I've got to maybe do even a better job at figuring these moments out, because the opportunities were there today, for instance.

"They were there in other moments as well this season, maybe Indian Wells or Wimbledon or whatever. That can change an entire season around, the confidence around, the flow of things. But, you know, I'm happy how I played this season, and I'm extremely excited for next season."

Photo credit: Julian Finney/Getty