AFP/Getty Kobe Bryant and Shaquille O'Neal
NBA Hall of Famers Shaquille O'Neal and Kobe Bryant — who played together from 1996 to 2004, winning three consecutive championships for the Los Angeles Lakers in the early 2000s — famously feuded during their time as teammates. Personality clashes and disagreements over their respective roles ultimately contributed to O'Neal being traded to the Miami Heat, breaking up a one-two punch that some consider the best in basketball history.
And although the two were able to put aside their differences and thaw the iciness between them in later years, O'Neal — the subject of SHAQ, a four-part HBO docu series out Nov. 23 — admits Bryant's tragic death in a helicopter crash in Jan. 2020 has left him with many regrets regarding things left unsaid.
"You put off [getting in touch]," O'Neal, 50, tells PEOPLE in this week's issue, on newsstands this Friday. "I'll never get to see Kobe again, in real life, forever. And I just should have called. He should have called. We both should have called. But he's working, I'm working, so it's 'I'll see you when I see you.' "
O'Neal famously memorialized Bryant and his daughter Gigi — who also died in the tragic crash at age 13 — at a celebration of life event held at the Staples Center a month after their deaths.
"As many of you know, Kobe and I had a very complex relationship through the years," O'Neal said in his speech, "but not unlike another leadership duo, John Lennon and Paul McCartney, whose creative rivalry led to some of the greatest music of all time."
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"Kobe and I pushed one another to play some of the greatest basketball of all time… And, yes, sometimes, like immature kids, we argued, we fought, we bantered or insulted each other with off-handed remarks," O'Neal continued. "But make no mistake, even when folks thought we were on bad terms, when the cameras were turned off, he and I would throw a wink at each other and say, 'Let's go whoop some ass.' "
O'Neal says he and Bryant always maintained a deep love and respect for each other, but he acknowledges to PEOPLE that time has yet to give him more perspective on his teammate's passing. "[I thought], 'We're both going to get old. We'll both be at the 50-year Lakers anniversary.' Other things shouldn't have been more important [than getting in touch], but little things [got in the way]."
His simple advice for others feeling disconnected from friends and loved ones: "Call your mom. Call your brother. Call the homeboy you used to party with in college. Forever is a long time."
For much more with Shaquille O'Neal, pick up the latest issue of PEOPLE, on newsstands Friday, or subscribe here.