When his left knee buckled the summer before his senior season at Las Vegas High School, Ray Smith vowed to return stronger than ever the following year.

When the same fate befell his right knee during practice before his freshman year at Arizona, Smith once again tirelessly dedicated himself to the rehab process.

Only after suffering an ACL tear for a third time in less than 30 months did the former five-star recruit concede it was time to hang up his jersey and basketball shoes for good.

Smith announced his retirement from basketball on Thursday after an MRI exam confirmed that the right knee injury he suffered during an exhibition game on Tuesday night was as serious as he had feared. The 6-foot-8 forward tore his ACL and suffered other ligament and meniscal damage, injuries that would have sidelined him for the entire 2016-17 season even if he had decided to keep playing.

“My run in basketball has been great,” Smith said in a Tweet thanking those who have helped him throughout his career. “My father once told me that just because someone is a good basketball player doesn’t make them a good person. That the sport doesn’t define who we are, only what we can do. I love the game of basketball, but I have decided to step away from the game for good.

“I will still be involved with the team and I will still attend THE University of Arizona. Pretty much what I’m saying is thank you BASKETBALL, you’ve been GREAT! But the 6-8 long, athletic wing that can play multiple positions is out. *DROPS THE MIC*”

Smith suffered the injury midway through the second half on Tuesday night when he went up for a layup, landed awkwardly and crumpled to the ground. Arizona coach Sean Miller feared the worst as Smith had to be helped off the floor and further testing confirmed his suspicions.

“In the 25 years I have been a college basketball coach, I have never felt as helpless as I did when I saw him go down on Tuesday night,” Miller said in a statement released Thursday by Arizona. “No 19-year-old kid should have to experience three season-ending injuries in a 30-month period of time.

“I have watched Ray work with our strength and conditioning coach tirelessly for two years. I have seen him in our training room around the clock, doing everything he can to play the game he loves. To witness his extraordinary efforts and see this happen to him once again is beyond disheartening.”

While Smith’s future away from basketball should be very bright, his absence is a blow to an Arizona program that hoped to contend in the Pac-12 and nationally this season. The Wildcats aren’t as deep or as versatile defensively without the 6-foot-8 combo forward.

Smith’s injury is the most dire news of what has been a rough preseason for Arizona. Leading returning scorer Allonzo Trier’s eligibility this season is in question after he sat out Tuesday’s exhibition game for unspecified reasons, while promising backup center Chance Comanche is suspended indefinitely for academic reasons.

Being down to seven healthy scholarship players is a major concern for Arizona, but the Wildcats can learn from Smith’s positivity. On the night of his injury, Smith tweeted, “Thanks to all the fans but I’m blessed man to even be where I am. One of my lil bros from vegas was murdered in his apartment the other day.”

In his statement, Miller emphasized that Arizona will continue to support Smith.

“Ray is surrounded by a community that loves Arizona Basketball, current and former teammates that look at him as a brother, and a coaching staff and family that is beyond supportive and forever with him,” Miller said. Although the mountain that Ray is climbing continues to change, my belief in him to be a resounding success in life has never been stronger.”

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Jeff Eisenberg is the editor of The Dagger on Yahoo Sports. Have a tip? Email him at daggerblog@yahoo.com or follow him on Twitter!

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