Rana was seen with heavy strapping to his thigh in the warm-up clash against South Africa on Wednesday and "doesn't look good", according to India captain Suryakumar Yadav.
"He is not ruled out yet," Suryakumar said. "He's being assessed by the physios. But I think, today we'll know what's going to happen. But it doesn't look good, it's not that great.
"Don't worry, we have 11 players for tomorrow. But it's a big blow obviously because you make a squad of 15 players with a lot of combinations in mind. So we made it with the same thought.
"And if he is not available for us going forward, then we will set other combinations, however can we do it.
"But we have enough players, enough combinations, which we can make against all the teams for this tournament. But if we miss him, we will definitely miss him."
The 24-year-old Rana is important to the India T20 side as he provides a third seam-bowling option which allows them to pick and extra spinner.
He also is a proper batter that comes in at number 8 to give a powerful top-order the necessary depth to go hard upfront.
"We will see which fast bowlers have done really well for the last one or two years," Suryakumar said. "And which bowler can bat as well. But there is no hard-and-fast rule that he has to bat.
"Because if you are expecting someone at No. 9 or 10 to come and hit a six, then what do you have the top eight for. But we will see whom to pick. We do have a few options but we will pick the best one."