BOSTON -- Jimmy Butler still believes the Miami Heat are going to close out the Boston Celtics and advance to the NBA Finals despite two straight losses that have cut their series lead to 3-2.

After a 110-97 Game 5 loss Thursday night inside a raucous TD Garden, the Heat have lost by a combined 30 points over the past two potential close-out games. So why is Butler, who walked around the outside of the locker room calmly eating popcorn after the game, still so confident about his team's chances?

"Because the last two games are not who we are," he said. "It just happened to be that way. We stopped playing defense halfway because we didn't make shots that we want to make. But that's easily correctable. You just have to come out and play harder from the jump. Like I always say, it's going to be all smiles and we are going to keep it very, very, very consistent, knowing that we are going to win next game."

For one of the first times throughout his torrid postseason run, Butler did not live up to the sky-high standard he has set for himself over the past month, scoring 14 points on 5-of-10 shooting from the field as the Celtics dominated from start to finish.

"Our offense was disjointed a little bit," Heat coach Erik Spoelstra said. "We weren't able to initiate our offense, get the ball where we needed it to go in spots where you could operate. If we can get Jimmy in his comfort zones and strength zones more consistently, he'll be just fine."

That was the sentiment throughout a Heat locker room that wasn't panicking despite the fact that the No. 2 seeded Celtics are playing with a renewed sense of confidence on both ends of the floor.

"I think just give him a steady diet, and we know that he'll find it," Heat big man Kevin Love said of Butler. "Just based off of who he is, based off the numbers, we have no doubt in Game 6 he'll come out and be Jimmy Butler."

The calmness Butler showed after the Heat's past two losses seemed to be permeating throughout the locker room, where his teammates expressed trust that they will still be able to find their way, especially if guard Gabe Vincent, who missed Game 5 because of a sprained left ankle, is able to return in Game 6.

"Why would we lose confidence?" Heat center Bam Adebayo said. "When we started this journey, nobody believed in us. Everybody thought we were going to be out in the first round. Everybody thought we were going to be out in the second round. And now we are here one game away. For us, we've always had confidence, and that's not going to go away."

Spoelstra didn't buy into the notion that his team was going to have an emotional letdown.

"Who cares about mood?" Spoelstra said. "We have a gnarly group. I think so much of that is overrated. It's a competitive series. You always expect things to be challenging in the conference finals. One game doesn't lead to the next game. Based on all the experience that we've had, it doesn't matter in the playoffs. It doesn't matter if you lose by whatever.

"We beat them by whatever in Game 3. It just doesn't matter. It's about collectively preparing and putting together a great game. We'll play much better on Saturday. That's all we just have to focus on right now."

So will Game 6 on Saturday night in Miami feel like a Game 7?

"No, it feels like a Game 6," Love said with a chuckle. "But they're a hungry team. And being down 3-0 and getting a win at our place and then getting a win here you can tell they're fighting for everything, clawing for everything, and now both teams are going to be feeling that, so we need to come out and have a great showing and set the tone at home."

And the key to doing that Saturday night will be to get Butler rolling quickly after being held in relative check in Games 4 and 5.

"We've just got to play better," Butler said. "Start the game off better, on the starters, make it more difficult for them. They are in a rhythm since the beginning of the game. But we are always going to stay positive, knowing that we can and we will win this series. We'll just have to close it out at home."