Baker has been the Cowboys' leading scorer and best player the past two seasons, and they have struggled since he injured a groin in late December.
He had all 11 of their second-half points Wednesday night before severely spraining his right ankle on a drive to the basket with about seven minutes left and Tech leading 55-43.
But others then began playing better, and the Cowboys' pressure gave Tech trouble and fueled the comeback.
"With Mo going out, everyone stepped up their game," said Victor Williams, who scored all 10 of his points over the final 6:10. "We showed a lot of people we can win without Mo. I think that's a big statement for us."
Baker is questionable for the Cowboys' game Sunday at Fresno State. He will receive treatment and not practice for the next couple of days.
The Cowboys (18-5, 5-5 Big 12) had lost four of their previous six games and this one appeared lost as well because they couldn't find a way to stop Andre Emmett.
Emmett had 29 points, three fewer than he had in the Raiders' 94-70 victory over Oklahoma State on Jan. 19.
But after Emmett scored to make it 57-47 with 6:02 to play, the Cowboys ran off 12 straight to take a 59-57 lead. The Raiders (16-5, 5-4) had three turnovers and missed two shots during that time.
"We've had a problem all year long in several different games where we've gotten a lead and then it's like, 'Well, this game's over,"' coach Bob Knight said. "It's like we're bringing Randy Johnson in to pitch for the last three outs, and that just doesn't happen."
Two free throws by Emmett with 3:04 remaining tied it at 59, and a free throw by Andy Ellis gave the Red Raiders a 60-59 lead with 2:14 to play.
Williams then hit a free throw and followed that with a layup off another Tech turnover, making it 62-60. Kasib Powell, who scored 17 points, tied it again with a jumper with 29 seconds to play.
After a timeout, Williams got an open jumper from the left wing. The ball hit the front of the rim and Crawford was there to drop it back in.
"I just went and tried to get a tip-in because I knew it might come off short," Crawford said.
Knight opted not to use a timeout, and Will Chavis' 15-footer in traffic at the other end came up short and set off a players' celebration on the court.
"Every mistake we made, they took advantage of," Knight said. "They just played really well down the stretch, played much, much better than we did down the stretch."
Oklahoma State, which had scored 21 and 17 points in the first half of its previous two games, had 22 by the 11:42 mark before cooling off. They made 10 of 11 shots to build a 22-12 lead, then made four field goals in the next 17 minutes.
"It looked like we were really in trouble," Cowboys coach Eddie Sutton said. "But the press got us back in the game, we loosened up offensively and we were able to hit some shots."
Baker finished with 19 points, but Sutton said the ankle sprain was severe and would likely keep Baker out until at least next week.