Miguel Montero had broken his right index finger back in winter ball, and has only recently healed fully. He is active for Wednesday night's game, but will not appear in the starting lineup.
The Arizona Diamondbacks will now feature three catchers on their 25-man roster, as outfielder Alex Romero was optioned down to Triple-A Tucson rather than utility player Robby Hammock.
Romero had gone 3-for-10 in 12 games with the Diamondbacks, but only made one start when Chris Young was scratched from Sunday's lineup with flu-like symptoms. The organization would rather have Romero see everyday action in Tucson to aid his development than continue to use him as a bench player in the big leagues.
The moves leave Jeff Salazar and Chris Burke as the club's primary outfield backups.
The Arizona Diamondbacks had the best record in baseball at 15-5 when Montero was activated. Doug Davis (thyroid cancer) and Chad Tracy (microfracture surgery) have yet to contribute to the team's fast start, either.