"For sure we missed him; I don't look at it that way with the penalty kill last night," he said. "We've got to do a better job killing whether he's in the lineup or not. But we're definitely glad to have him back."
Sundqvist has become a key penalty killer, and more, in his second season with the Blues.
During the regular season, the 6-foot-3, 209-pound Sweden-born forward had an NHL career-high 31 points (14 goals, 17 assists) in 74 games, averaging 13:49 of ice time per game.
In 21 Stanley Cup Playoff games, he has nine points (four goals, five assists) while averaging 15:54 of ice time per game.
"He's been one of the huge bright spots for our team all year," forward Brayden Schenn said. "He's been an unsung hero for us, whether it's filling in on the power play, huge on the PK, scoring goals. He's had a great season so far.
"We expect a boost from him. He's playing really good hockey for us right now. He's doing a good job on the penalty kill and he's hard to play against. Obviously, we missed him last game and we're looking forward to having him back next game."
Sundqvist's return for Game 4 will present Berube with a difficult lineup decision because forward Zach Sanford, who took Sundqvist's spot when he served his one-game suspension, played well in Game 3. Sanford, who had an assist and was a plus-one in the loss, is likely battling forward Robby Fabbri for a spot in the Blues lineup Monday.