Every Celtics’ fan worst nightmare became reality Tuesday when Jayson Tatum’s left ankle turned awkwardly after he delivered what was essentially a game-winning pass during the closing seconds of Team USA’s overtime win against Turkey at the FIBA championships.

Tatum grimaced in pain and needed the help of two Team USA staffers to limp off the court. The team later announced that Tatum had a left ankle sprain and would be reevaluated on Wednesday.

Here's Jayson Tatum's ankle injury at the end of Team USA's win over Turkey. pic.twitter.com/IrUadQz1DE — Chris Forsberg (@ChrisForsberg_) September 3, 2019

The swift and understandable reaction from Boston fans was to scream that this is exactly why you don’t want your team’s players involved in international basketball. But offseason injuries are not FIBA exclusive and while it’s certainly a danger that players take to play for their country, the reward almost always outweighs that risk.

Where else this summer would Tatum be standing in front of a hostile crowd full of Turkey supporters shooting must-have free throws in the closing seconds of regulation? Tatum drew a foul with 0.1 seconds remaining in the fourth quarter and Team USA down by 2, then made two of his three freebies just to prevent the Americans from an embarrassing group-play defeat.

Where else this summer would Tatum find himself needing to push the ball up the court and make the right decision with his team down by one in the closing seconds of overtime? Tatum collected a monster rebound of a missed free throw and, with eight seconds to go, pushed the ball up the court before a little bounce pass put Khris Middleton at the free throw line to win the game.

Tatum’s left ankle bent awkwardly as he neared the charge circle on that transition feed after a Turkish defender rushed in front of him to foul Middleton. Tatum crumpled to the floor and Celtics fans will cling to hope that it’s the sort of sprain that will heal before Boston convenes for the start of camp later this month.

There will be consternation now that Tatum was on the floor. He will become the poster child for why the NBA’s biggest names bailed on this year’s tournament. It’s simply an overly emotional response.

Even Celtics coach Brad Stevens brushed off the notion that an injury was the team’s biggest fear when allowing players to participate in international basketball.

"I don’t even really think about [the potential for injury],” Stevens told reporters at a community event Tuesday morning after Tatum’s injury. "I think at the end of the day, they’re going to be playing 5-on-5 other places. I don’t think you can get any better [playing in the summer] than doing what those guys are doing. They’re playing in environments where everybody’s rooting against them, in tight games. And I always say that the first road game of the year, it hits you like a ton of bricks. These guys are doing it in late August, early September.

"I got a lot of a lot of admiration for [Team USA’s] staff… and I think [the players are] doing a great job. Kemba [Walker] was amazing in the fourth quarter today and overtime today [versus Turkey]. And then Tatum obviously made huge plays. We’re hopeful that [the ankle injury is] nothing major but we don’t know yet.”

Tatum shook off a somewhat disappointing exhibition stint with Team USA to play two very good games against Turkey and the Czech Republic to open group play. When it looked like Team USA was going to collapse against Turkey, it was Tatum and new Celtics teammate Kemba Walker who saved them each time. Tatum and Walker scored or assisted on all 12 of Team USA’s points in overtime with the duo pairing up for seven straight points after the Americans fell behind by five with under three minutes to go.

The ankle injury is frustrating, if for no other reason that it will rob us all of an opportunity to see Tatum further emerge on a big stage. He started both games so far in group play and, despite some struggles finishing at times, the flashes he showed were incredibly positive regarding his potential this coming season.

Tatum’s absence could open the door for more time for Jaylen Brown and Marcus Smart. Celtics fans, gun shy now after watching Tatum roll his ankle and still not quite over Gordon Hayward’s horrific ankle injury from the 2017-18 opener, will watch the rest of the games with their eyes partially covered hoping no one else gets dinged up.

Injuries happen. Tatum will be a better player next season because of his Team USA experience. That much is obvious simply from the play he injured himself on.

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