Lamar Jackson caught fans by surprise Monday night when he left in the fourth quarter of the Baltimore Ravens’ game against the Cleveland Browns only to come back to play the hero and pick up the win.

Jackson explained that he wasn’t in the locker room to poop, but rather he was experiencing cramping – something he says is "probably" coronavirus-related when he was asked about it Wednesday.

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"Probably because of the body heat," Jackson added, via the team’s website. "We were running in the cold – it was so cold out there. That probably had an effect on it as well. But I can't call it."

Ravens coach John Harbaugh listed several reasons why he could have been cramping.

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"Who knows. Is it that [COVID-19]? Is it the nutrition, the diet?" Harbaugh said. "It's quite a mystery. I think the doctors are trying to figure all that stuff out too."

Jackson reportedly tested positive for the coronavirus over Thanksgiving and missed some time, as did plenty of his teammates, as he battled the illness. He said after the game that the cramps were severe.

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"I was real-life cramping, like my hand, my throwing arm cramping, forearm cramping, fingers getting stuck together," he said Monday. "I was going through it. I was ticked off."