The Miami Heat have been on a tear of late, entering Martin Luther King Jr. Day having won 12 of their last 15 games — including seven straight — to surge up to fourth place in the Eastern Conference. Their roll got slowed a bit on Monday, though, as guard Tyler Johnson went down in serious pain after an awkward landing in the lane midway through the third quarter of Miami’s meeting with the Chicago Bulls:

Johnson drove into the paint and elevated, attacking Bulls center Robin Lopez head-on. The two collided in mid-air, and as Johnson tried to double-clutch and loft in the left-handed runner, his left leg got tangled around Lopez’s right foot, and he came down hard. Johnson immediately winced and reached down for his left knee, writhing in pain along the baseline.

“I was really worried,” said Heat point guard Goran Dragic after the game, “because I’ve never seen Tyler stay down like that.”

Johnson couldn’t leave the floor under his own power, and eventually needed to be helped into a wheelchair and carted back to the locker room:

Shortly after his exit, the Heat removed any mystery from the proceedings:

Johnson finished with 10 points, three assists and one rebound in 20 minutes of work before exiting. The Heat made a big push after his exit, scoring 39 fourth-quarter points, but couldn’t get over the hump, falling 119-111 to Chicago to snap a seven-game winning streak.

“It’s actually the back of his foot, his ankle,” Heat head coach Erik Spoelstra said, according to Ira Winderman of the South Florida Sun Sentinel. “Everything was fine with that, so the first part of the news is he’s relieved. We’re all thinking worst, but we’ll see if we can get an MRI tomorrow. Right now, he just has it wrapped in tape, so that’s a good sign, as well. But we’ll know more.”

It’s heartening that X-rays were negative, though it’s worth noting that Johnson left the arena on crutches and wasn’t made available for post-game comment. Still, Johnson going down deals another blow to a Miami backcourt that’s gotten awfully thin.

“It seems like all the twos are going down,” Dragic said, according to Barry Jackson of the Miami Herald. “Rodney [McGruder], Dion [Waiters]. Hopefully, nothing serious with Tyler.”

The injury to Waiters had pushed Johnson into the starting lineup; he entered Monday averaging 15.5 points, 4.5 rebounds and 2.5 assists in 35.2 minutes per game in 11 starts. If Johnson misses significant time, Spoelstra could have to bide time until McGruder’s return by moving swingman Wayne Ellington into the first five. But he might prefer to keep the veteran reserve in the now-familiar bench role in which he’s grown comfortable enough to shoot 40 percent from beyond the arc. In that case, Spoelstra would likely look to slide a forward into the starting five alongside Josh Richardson on the wing.

He could go with former starter Justise Winslow, whose spotty shooting stroke has led to him more frequently being deployed up a spot as a small-ball power forward. Or he might opt to take a chance on recent addition Derrick Jones Jr., who’s still trying to make his mark on the NBA level after spending most of last season in the D-League and getting waived by the Phoenix Suns in early December, but who’s also a remarkable athlete with quickness and length (he stands 6-foot-7 with a 7-foot wingspan) who seems like a hand-in-glove fit for the Heat’s hard-charging attack.

Lots of people were surprised when Miami chose to match the $50 million offer sheet the Brooklyn Nets gave Johnson when he hit restricted free agency in the summer of 2016. (Johnson, famously, was more surprised than anybody.) But the 25-year-old combo guard has proven a dependable, talented, versatile part of Spoelstra’s rotation, averaging 13.2 points, 3.9 rebounds, 2.8 assists and 1.0 steals in 29.8 minutes per game over the past two seasons in Miami. He’s a key part of Miami’s on-court culture of toughness and relentlessness; whichever path Spoelstra takes to replacing him in the short term, the Heat will be hoping that the MRI results are favorable, and that his return will come sooner rather than later.

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Dan Devine is a writer and editor for Yahoo Sports. Have a tip? Email him at devine@oath.com or follow him on Twitter!

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