And he let his squad know it after Martin St. Louis scored a tiebreaking goal in the third period to give Tampa Bay a 2-1 victory over the Senators.
"Some will say we won that one," Boucher said. "We did bounce back, but I want a lot more than that.
"We usually come out with a lot more desire than that. We need to be better," he added.
Adam Hall added a goal for the Lightning, who got 31 saves from Dwayne Roloson.
Zack Smith scored the lone goal for the Senators. Brian Elliott stopped 25 shots.
The Senators, coming off a 3-2 shootout loss to the Chicago Blackhawks on Friday, got off to a slow start. They were being outshot 7-1 halfway through the first period.
"We have standards on our team and he wants the best from us in every game," Steven Stamkos said of his coach. "At the end of the day it's a win for us, but we just need to start better, have that focus from the start of the game and that's what Guy said to us pretty loudly."
Despite the Senators' offensive struggles, Ottawa's penalty-killing was solid against the Lightning late in the first after Jarkko Ruutu took two minor penalties on the same shift. Elliott made a number of big saves, including one on Stamkos.
Roloson, acquired by the Lightning last week, was solid in the second period. He made saves on Milan Michalek and Nick Foligno, but he was unable to stop Smith.
"We had so many chances so you've got to give Roloson some credit," Foligno said. "I think if we continue to play like that we'll start getting some wins."
The Senators took a 1-0 lead with less than three minutes remaining in the frame as Jesse Winchester -- on a 2-on-1 break -- fed a perfect pass to Smith, who beat Roloson low to the stick side.
"When you're losing it's definitely an uphill battle to get back on the winning end," Smith said. "We're confident we will and once we do I think we'll be able to capitalize on the chances."
Tampa Bay forward Dominic Moore took advantage of a giveaway by Alexei Kovalev just inside Ottawa's blue line early in the third. Moore carried the puck just to the right of Elliott, dropped it back to Hall -- who was left alone -- and had a wide-open left side to tie the game.
The Lightning took the lead at 5:43 of the third on St. Louis' 18th goal. On that play, Senators forward Mike Fisher was injured while blocking a shot and left the game. Fisher returned for one shift, but was then done for the night.
The Senators made a mad scramble to tie the game in the closing seconds, but couldn't force overtime.
"It's frustrating," Ottawa's Chris Campoli said. "It's not easy what we're going through, but there are some signs that we're getting better. ... We ran into a hot goalie so I don't think we deserved our fate."
The Senators were without G Pascal Leclaire (lower body), C Jason Spezza (shoulder). ... D Matt Carkner was a healthy scratch for the Senators. ... The Lightning were without G Mike Smith (knee), C Mattias Ritola (ear).