San Antonio Spurs power forward Tim Duncan retired on Monday after 19 incredible seasons in the NBA with five unforgettable championship runs. We know a lot about Tim Duncan – he stands at 6’11″, he is known as the “Big Fundamental,” and many of his former teammates call him the “best teammate ever.”

However, there is one thing we didn’t know about the future Hall of Famer– he is a huge Chicago Bears’ fan.

Former Bears’ beat writer, Michael Wright, now covers the Spurs for ESPN and has been able to document Duncan’s love for the Monsters of the Midway.

“We weren’t allowed to take pics in the locker room,” Wright tweeted. “But Tim Duncan always kept a Bears’ mini helmet and a Bears’ box in his locker.”

At first the news didn’t make sense. How is a guy who grew up in the Virgin Islands, went to college at Wake Forest in North Carolina and played for a Texas team for 19 years a die-hard Chicago Bears fan?

Then it came full circle.

Duncan grew up in the Virgin Islands during the 80s, when the Bears were a dominant team led by running back Walter Payton and head coach Mike Ditka. Since the Bears were thought to be a Super Bowl favorite year-after-year, they were the team that was always shown on national television. Since Duncan could not get NFL Sunday Ticket in the Virgin Islands, he became a fan of the team he watched the most – the Bears.

Despite living in Texas, a state known for football, his fandom remained strong for the Bears.

In 2007, the Chicago Bears were playing the Seattle Seahawks in the Divisional Round of the NFC Playoffs. The game went into overtime and Duncan had his team flight delayed, so he could watch the remainder of the game. And of course, the Bears would win the game on an overtime Robbie Gould field goal. Apparently, Duncan was going up and down the aisle of the Spurs team plane cheering as his team advanced to the NFC Championship.

“Let’s just say Tim was the last one on the plane,” Spurs head coach Gregg Popovich said to the San Antonio media.

Now that Duncan doesn’t have to play basketball on a daily basis, there is a strong possibility he might make an appearance at Soldier Field for a game this season.