Tulowitzki left Tuesday's 3-2, 11-inning loss after the top of the fourth, and X-rays showed a contusion.
"The best-case scenario is the MRI looks good and I'll try to get the swelling down and play soon," Tulowitzki said.
Tulowitzki was not in the starting lineup for Wednesday night's game against the Astros, and early indications are it will be at least a couple of days before his return becomes viable. Clint Barmes moved from second base to shortstop and Ian Stewart started at second on Wednesday.
When the injury occurred is unclear. Tulowitzki participated in an afternoon session before batting practice. He admitted the hand was sore then, and he iced it before the game. During the game, he couldn't hold onto his bat after a checked swing, and could barely keep the bat in his hands during a fly ball to center.
Tulowitzki has slumped all season, and has been participating in frequent practice sessions. That leads to overuse questions.
"I definitely took a lot of swings in the cage trying to work on things, so it's a possibility," he said.
In other injury news, right-handed reliever Matt Daley, at Triple-A Colorado Springs while on the disabled list with a sprained left foot, threw his second scoreless appearance Wednesday afternoon. He struck out one and gave up a hit in the Sky Sox's 3-1 loss to Fresno.
Thomas Harding is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.