BOSTON -- Celtics guard Marcus Smart will make his return in Game 4 of Boston's Eastern Conference semifinal series against the Milwaukee Bucks Monday night at TD Garden.

Smart, who suffered a torn left oblique four weeks and a day ago after running into Orlando Magic center Nikola Vucevic's left hip, had said Sunday he was "hopeful" he would return after going through practice for the first time since the injury occurred.

He's back pic.twitter.com/DHAog0TS1w

— Boston Celtics (@celtics) May 6, 2019

"Feeling good today," Smart said after taking part in Boston's practice. "Today was a good day. I was able to participate with the team. ...The boxes are being checked.

"We're taking it one day at a time but we're definitely in the right position, right time, progressive phase to where I'm getting really close to coming back here."

Smart's timeline shifted from "really close" to "arrived" late Monday afternoon, when the Celtics announced shortly before Celtics coach Brad Stevens' pregame presser that Smart had been upgraded from questionable to available for Monday's game.

Stevens had previously said Smart would play in short bursts, likely 4 to 5 minutes long, and added that it wasn't expected he would immediately go back into the starting lineup.

Getting Smart back is a massive boost for Boston, which enters Monday's game trailing 2-1 in the best-of-seven series after losing both Game 2 in Milwaukee and Game 3 in Boston Friday night. Smart, the team's emotional leader, also was arguably the best defensive guard in the league this season -- something the Celtics could use against Khris Middleton and Giannis Antetokounmpo's two-headed attack.

It was Smart's return from a thumb injury in Game 5 of Boston's first-round series with Milwaukee last year that helped swing that series in Boston's favor. The Celtics will be hoping Smart can provide them a similar boost this time around.