Milos Raonic teamed up with The Player's Tribune, a media platform that presents the voices of professional athletes, to write a "Letter to My Future Self." It's an introspective and inspiring look into the mind of the 26-year-old Canadian, mainly about his fears of mediocrity and regret.

"My biggest phobia at this point in my life is the possibility that someday I’ll look back and feel like I didn’t realize my full potential as a player," Raonic writes. "That I didn’t get to No. 1. That I didn’t win the multiple Slams.

"That I missed out."

Raonic had the best season of his career in 2016, achieving a career-high ranking of world No. 3, reaching the semifinals of the Australian Open, ATP World Tour Finals, and multiple Masters tournaments. At Wimbledon, he became the first Canadian man to reach the final of a Grand Slam.

For someone whose dream in high school was to be in the Top 50, it may seem strange to think of this success as "mediocre." However, according to the letter, that's kind of the point.

"You’re so close, but it feels so far—the steps are taller and the spotlight is so much brighter. And it’s making you that much more nervous," he writes. "Suddenly, the road from No. 4 to No. 1 feels longer than any road you’ve ever taken. You’re struggling to learn how to relax without giving in to the fear of failure.

"All these years from now, I hope you haven’t forgotten how much you embraced the climb — from being unranked, to cracking the Top 50, to now."

No matter what happens, everyone would agree that Raonic is has some of the biggest potential on tour right now and may just make that No. 1 ranking he so fervently talks about.

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