BRIGHTON, Mass. - As Celtics players stewed in the visitor’s locker room following the loss in Portland on Sunday night that ended a dismal 1-4 road trip, veteran Marcus Smart addressed his teammates, demanding that players stop making excuses for the team’s uneven play and begin putting in the effort necessary to thrive.

Smart, who could be seen visibly upset on the bench as the Celtics lost in Utah on Friday night, said his frustrations had been building throughout the lackluster trip and he thought somebody in the locker room needed to verbalize that Boston’s underwhelming play was unacceptable.

"I hate losing. I probably hate losing more than I love winning,” Smart told NBC Sports Boston after practice Tuesday at the Auerbach Center. "Especially with the team that we have and the potential that we have, we shouldn’t be losing games that we know we should win. Let alone, getting down 20 early and putting more pressure on ourselves and more stress on ourselves to come back.”

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His message to the team?

"Just that we can’t be OK with being fighters. Brad came in and he gave us the whole speech about, ‘You know you guys are fighters, you’re resilient,' for us to keep coming back down 20. But, as a team, I just felt like we shouldn’t even accept being down 20 and having to fight to come back. And there’s only so much that Brad and the coaching staff can do.

"We cannot be OK with that. We have to look ourselves in the mirror, look at one another, hold each other accountable, and figure out what’s going on.”

Even Smart isn’t sure what exactly is wrong with the Celtics but both he and his teammates have suggested that it might simply boil down to not putting forth the sort of effort and energy necessary over the full 48 minutes. Smart, who was one of the Celtics’ more consistent energy-givers on the five-game trip, said he felt like someone other than the coaching staff had to tell the team that they needed to figure it out.

"We needed to hear something because obviously what we’re doing isn’t working,” said Smart. "The norm of just coming in and, ‘Hey, we’re going to figure it out.’ The definition of insanity, everybody knows, is doing the same thing over and over, expecting a different result. So it’s insane.

“It’s something that I just felt like, I was tired of it so I know those guys were. So I just said what was on my mind. I’m sure everybody else was thinking it, but I just said it. I hope they didn’t take it the wrong way and I hope it gives us the boost that we need because we have a chance to be really great. But not at the rate we’re going.”

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Stevens wasn’t surprised to find out that Smart had tried to light a fire under his teammates.

"I've seen nothing change about Marcus Smart since he walked in the building. He's been that way since he got here, and he's been willing to step up and say things since he's been here,” said Stevens. "He wears his heart on his sleeve, as you all know, and he's extremely passionate.

"But he hates to lose. Obviously, we all do, and it's been a tough stretch. We've played good teams. They've outplayed us. And, at the same time, Marcus is a guy whose voice you expect to hear.”

Smart, the No. 6 pick in the 2014 draft, is easily Boston’s longest-tenured player. Now in his fifth year, Smart said he felt the locker room simply needed to hear a voice speak up.

"I expect, if they feel like I’m not doing my job, to say something to me as well,” said Smart. I feel like as a team, we weren’t doing our job — as a team. So I felt like we should hear that. I wasn’t going to wait for anybody else to say it. That’s kinda the thing, everybody waits for somebody else to do it, but it could have been done by you. So I just decided to say it.”

Smart said it’s unfathomable how Celtics players can come to practice each day and beat each other up, playing a high level of basketball, and then look like a shell of themselves in games. He wants that to change immediately.

"We come into practice every day and we beat each other up,” said Smart. "Then we get out there and it’s like, ‘Oh, we’re not going to beat these guys,’ or, ‘We don’t want to fight.’

"We're no longer the hunter. We’re the hunted now. Everybody is coming after us, everybody sees and reads what’s been said and what we’ve done. And, rightfully so as competitors, they take it as a disrespect to them, they want to go out and prove what they can do, so we’re going to get everybody’s best game. And if we’re not expecting that then, we’re going to continue to keep going into these deficits and getting our ass kicked.”

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