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Rod Carew

Rod Carew nearly died in September 2015 when he sustained a massive heart attack on the golf course. Fifteen months later, Carew received a heart transplant.

The heart had belonged to former Stanford and NFL tight end Konrad Reuland, who was 29 when he died in December from a brain aneurysm.

While Reuland was growing up in Southern California, he attended the same middle school as Carew's kids and had once met the baseball Hall of Famer. HBO Real Sports takes a closer look at this remarkable story in its new edition that premieres Tuesday at 10 p.m. ET/PT. Here is a preview: