DeBrusk and Krug each sustained an upper-body injury during the Bruins' 4-1 win in Game 2 on Saturday and were considered day to day.
The best-of-7 series is tied 1-1.
RELATED: [Complete Bruins vs. Maple Leafs series coverage]
DeBrusk was at his usual spot at left wing on the second line during Boston's morning skate, alongside center David Krejci and right wing Karson Kuhlman.
"I feel better today," DeBrusk said Monday. "Better than anticipated to be honest with you. Yesterday was a good day. Especially after adrenaline runs out you always worry about how things are going to shape up."
DeBrusk was injured when he was cross-checked by Maple Leafs forward Nazem Kadri in the third period Saturday. Kadri received a major penalty for cross-checking and a game-misconduct and will have an in-person hearing with the NHL Department of Player Safety on Monday. An in-person hearing means the player can be suspended at least five games.
"I'm not too sure how it will affect the series, time will tell on that," DeBrusk said. "I'm not sure what the League is doing or what the verdict is, we're just more so focused on our game in here. It sounds cliche but it's true, we're just focused on next game, next shift."
DeBrusk has six shots on goal in two playoff games. He was fourth on the Bruins during the regular season with 27 goals.
Krug was on the second defense pair with Brandon Carlo during the morning skate. He has two assists in two playoff games and was fifth on the Bruins during the regular season with 53 points (six goals, 47 assists).
"Yeah, obviously really relieved. You always want to compete with your team and hopefully give them the best chance to win," Krug said. "So, nice that I'm able to feel well enough to play tonight."
Bruins defenseman Connor Clifton is out because of an upper-body injury sustained during Game 2. Replacing him in the lineup will be defenseman Steven Kampfer, who skated with Matt Grzelcyk during the morning skate.
Kampfer has played 201 regular-season games, including 35 with the Bruins this season, but the 30-year-old will make his Stanley Cup Playoff debut.
Forward Marcus Johansson, who didn't play Game 2 because of an illness, remains sick and unavailable for Game 3.