"We're not sure yet. We have to talk to him. He still hasn't swung much," Baker said on Tuesday. "There could be a rehab assignment in there, too."
Stubbs was scheduled to hit in the indoor cage and could take batting practice on the field Wednesday.
In his latest rehab assignment appearance, Reds left-handed reliever Bill Bray worked 1 1/3 innings and allowed one hit and struck out one over 22 pitches Monday night for Triple-A Louisville.
Bray has been on the disabled list since April 24 because of a left groin strain and, later, a back injury. When asked whether Bray could return Friday, when the Reds return home, Baker was non-committal.
"It depends on the quality of pitching," Baker said. "It depends on how he looks back to back. It depends on how many pitches he throws."
Bray has five rehab outings combined with Louisville and Class A Dayton and has given up two earned runs over five innings with two walks and nine strikeouts.