The Rockies also said Street's availability is "day-to-day."
Street was transported by ambulance to a local hospital after teammate Ian Stewart's liner hit him during batting practice before Tuesday's 4-2 loss to the Pirates.
Street, who was playing catch in the right-field corner at the time of the incident, felt some pain down his right leg and fainted "two or three times" in the 15 or so minutes before the ambulance arrived, according to head athletic trainer Keith Dugger. The ball left a black-and-blue mark.
According to the club's press release, Street was "lucid and responsive" when the ambulance arrived.
"I think his body actually kind of went into shock, because he actually said he wasn't in much pain," Dugger said. "The thing that was kind of alarming is that he said he had ringing in the ears. We don't know. Sometimes it's just a sign of shock. He could have held his breath and gotten this natural response."
Stewart saw his liner hit Street.
"I saw the whole thing," said Stewart. "They're playing catch out there, and I knew the ball was heading their way. I was just hoping it wouldn't hit anybody.
"I want to say I might have even hit 'Streeter' before, like in the leg, in BP. But I can't say for sure. It's just a freak thing. You hardly ever see someone get hit in BP. They're out there playing catch and supposed to be looking over between pitches, so I don't know what happened there.
"I didn't try to really speak to him. I said 'sorry' and that I hope he's all right. You say a prayer and then that's it, really."
Street missed the first 69 games of the season with shoulder tightness and a right groin injury. Since his return he is 1-2 with a 3.00 ERA and has converted six out of seven save opportunities in 14 appearances.
Thomas Harding is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.