In the 2013 NBA Draft, Giannis Antetokounmpo was selected by the Milwaukee Bucks with the 15th overall pick, and they haven't looked back since. Yet, the Boston Celtics had an opportunity to select him after they traded up in the draft, but they ultimately went for Kelly Olynyk instead.

As we approach the five-year mark since that draft, Olynyk is now with the Heat, while The Greek Freak has become one of the best young players in the NBA today. Obviously, hindsight is a wonderful thing, but many have wondered how the Celtics never saw how good of a player Giannis could become.

Speaking recently to the Boston Herald's Steve Bulpett, Celtics general manager Danny Ainge explained why his franchise passed on the Bucks star back in 2013, and surprisingly, the main reason was down to his size at the time.

Ainge said: "Giannis was a really bright talent. He was really young. He played on a pro B team in Greece, and I saw him practice. I met him. He was very skinny. I thought he was absolutely a worthwhile project.

"But never in a million years did I see him becoming a potential best-player-in-the-league type of player. And I saw his potential as a good player because he could handle the ball, and he was long. But he was really, really skinny, and I think he was about two or three inches shorter than he is now. But what an amazing player."

Sure enough, back in 2013, The Greek Freak was 6-foot-9 when the Bucks drafted him, but he quickly shot up to 6-foot-11 and has become one of the most dominant young players in the NBA today, with many believing he could win the MVP award one day.

Ainge continued: "But no doubt, he's a guy that potentially you could have had in a draft. We look back every year after the draft and after we see how guys develop. We try to figure it out. Sometimes when a guy evolves four or five years later, you know, those are really the guys you can't tell are going to become that.

"But Giannis was pretty good in his second year. I mean, he was a talented kid right away, but it was on losing teams. But by his second year, you could tell that he was pretty dang special."

The Celtics could end up regretting this decision for years to come, as it looks like Giannis is on the right path to be one of the best players in the NBA for the next 10-plus years.

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