Tommy Haas reached the quarterfinals in Stuttgart, defeating Roger Federer along the way. (AP)

Players come and go on the competitive ATP World Tour, but 39-year-old Tommy Haas has punched in the clock for more than 20 years. He knows what it’s like to be a highly touted young star and reach No. 2 in the world, and then to languish through numerous injuries and surgeries.

Haas came into Stuttgart this past week from seemingly off the grid and ranked No. 302. On Wednesday, he pulled off a surprise win over his good friend Roger Federer. His 6-year-old daughter Valentina cheered for her dad as if he was the greatest show on Earth. 

That’s why Haas keeps on playing.

This was a motivating factor for Haas back in 2013 after a mini-renaissance saw him defeat world No. 1 Novak Djokovic at Miami and eventually move up to No. 11 in the rankings.

At the time, Valentina was just 2 years old. Former mentor Nick Bollettieri, who helped develop a teenage Haas, told The New York Times, “I think there was some inner energy in Tommy that only a few people in life have. And I also believe that his daughter, their little girl, is driving him. He really wants his daughter someday to be able to say, ‘That was my daddy.’”

As 2017 began, Haas mounted another comeback after his ninth surgery forced him to miss 15 months from the tour.

 “It would be great for her to at least watch me a few times as my tennis career comes to an end," Haas said in February. "[For her] to understand and watch the whole match in the box, that is my main goal.”

Haas and his wife, actress Sara Foster, had a second daughter in November 2015, but he has said this season will be his last year playing on the pro tour.

Following the Federer victory, Haas lost in the quarterfinals to Mischa Zverev, and he held court with reporters for the last time in Stuttgart. Valentina sat on his lap with a smile that brightened the world and became another moment with her father that she will never forget. 

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