Black said no decision has been made on a potential replacement. MLB rules allow a player to be placed on a seven-day concussion disabled list. Wolters, 24, went on the list last year, as a rookie, on June 3 and returned June 15.
Wolters, batting .346, took the shot to the head, and on a subsequent pitch from Carlos Estevez committed a passed ball. After retrieving the ball, Wolters called out head athletic trainer Keith Dugger for a brief conversation, then left the game. Dustin Garneau replaced Wolters.
The Rockies signed veteran Ryan Hanigan to a Minor League contract late in Spring Training. Hanigan carries a .282 batting average at Triple-A Albuquerque. Also at Albuquerque is Anthony Bemboom, a Triple-A phase Rule 5 Draft pick, who is hitting .244. There is room to add a player, since the 40-man Major League roster is at 39 after infielder Cristhian Adames was designated for assignment on Sunday.
With Wolters' injury and Tom Murphy (hairline fracture, right forearm) out, Garneau is the only healthy catcher on the 40-man roster.
Thomas Harding has covered the Rockies since 2000, and for MLB.com since 2002. Follow him on Twitter @harding_at_mlb, listen to podcasts and like his Facebook page. This story was not subject to the approval of Major League Baseball or its clubs.