Butler missed his sixth consecutive game Tuesday night, a 113-100 overtime loss to the Knicks, after another flare-up of his strained left hip flexor during the morning shootaround.
Butler missed eight of 10 games before the All-Star break -- as well as the All-Star Game -- with the injury, and the Wizards had hoped he would be able to play after the long weekend of rest.
"He went pretty long in practice yesterday," coach Eddie Jordan said before Tuesday's game against the New York Knicks. "He went further along in practice than he had in the past.
"And yet we started shootaround, and that was enough. So there is some progress. There's going to be some setbacks here and there, and it was a setback."
The Wizards are 2-8 without Butler this season and had lost eight straight before a last-second win over the Los Angeles Clippers just before the break.
Jordan said he hopes Butler can return by the end of the week.
Thomas was cleared to have contact in practice Monday for the first time since his open-heart surgery in October. While Thomas' heart is fine, the workout showed that his sternum has yet to fully heal after being broken during the 4½-hour operation.
"He's going to have to get used to the contact, and that's going to be hard to do," Jordan said. "We went through some contact, and he felt he took a shot and he didn't really like the experience of that pain, so we might not see him for a while in some contact drills. We're going to give him some more time."
Also, point guard Antonio Daniels said he was going to have to live with his ankle injury for the rest of the season and that it might require surgery over the summer. Daniels missed two of three games before the All-Star break.
"It's about getting through this for me right now, just pushing the pain aside a little and being who I am," Daniels said, "trying to do a lot of strength work to get my acceleration back and my explosiveness back."
The Wizards need Daniels to play because Gilbert Arenas continues to recover from knee surgery. Arenas participated in light, non-contact drills Monday and hopes to return in March.
Daniels said he might have to take it easy in practice at times to get through the rest of the season.
"That's something that me and Coach Jordan have to talk about and discuss," Daniels said. "The most important thing for me right now is being here with my team."