BOSTON — Boston Celtics guard Terry Rozier believes that the team’s cross-country flight last week forced players to recognize that time was running short on salvaging an uneven 2018-19 season and that Kyrie Irving’s positive energy has been one of the biggest factors in steering the team back on course.

“It’s easy … when Kyrie is in a great mood, when Kyrie is feeling good, our whole team is feeling good,” Rozier said this week during an episode of The Pick Up presented by Nissan. The first of two episodes with Rozier airs Friday night during Celtics Post Up on NBC Sports Boston.

"And you know when [Irving is] feeling good, when he’s super engaged, he’s smiling, things like that. … When he’s a little upset, angry, whatever it might be — [with the] media, whatever -- everybody tends to get uptight and it doesn’t work out for us and I’m talking players, coaches, everything. He’s our leader, our guy, he’s our backbone.”

The Celtics have won four of their last five games since a long flight out west following a disheartening loss to the Rockets on national television. An engaged Irving hasn’t just been spectacular offensively the past five games, averaging 24.5 points, 9.8 assists, and 6 rebounds per game — highlighted by a 31-point triple-double in Thursday’s come-from-behind victory over the Kings — but he’s been taking charges again and making the sort of hustle plays that has reinvigorated Boston’s defense.

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And the tenor around the team changed with that flight to the Bay Area.

“The flight was super long, and after a loss, too, so it was just like -- obviously you had a group of guys, sectioned off with different groups, people talking amongst one another, and basically we just came to the realization that we have to get our stuff together. And you gotta get it together fast.

"This road trip was the perfect way to start off something special.”

It's become clear that Boston’s success starts with Irving and his engagement level. While everybody on the roster will play a part in what this team can ultimately accomplish, it all starts with Irving.

Rozier was asked if he’s surprised that outsiders weren’t aware of how important Irving’s demeanor is to this young team.

“Well, [outsiders] don’t understand a lot of things, to be honest with you,” said Rozier. "We in a locker room, we in a locker room. So we know what’s going on, 100 percent. We know everything. We know how people are feeling. Like, people on the outside looking in, they may see Jaylen [Brown] get into it with [Marcus] Smart, or [Marcus Morris], or Kyrie, and they might think that JB is the problem just because of what they see. We see everything, we know everything that’s going on.

"And whether it’s on the plane, whether it’s in the locker room, we see it all, because we’re a family and we are with each other 24/7. Same time, we know how to fix them problems.”

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