The Boston Celtics went back to their old ways during Game 5 against the defending champion Milwaukee Bucks on Wednesday, and that’s not good.

The Bucks returned the favor by rallying from a double-digit lead in the fourth quarter to post a shocking 110-107 victory at TD Garden to claim a 3-2 series lead in the Eastern Conference Semifinals. Boston won Game 4 in Milwaukee with a monster fourth-quarter comeback.

The Celtics got careless and lazy late in the game. They looked like the team of old, and the Bucks took full advantage.

The Boston Celtics gave one away against the Milwaukee Bucks

Maybe the Celtics got a little overconfident, but they’re the ones who should know better. Boston battled back from double-digit, third-quarter leads in Games 3 and 4 in Milwaukee. The Celtics came up short after taking the lead in Game 3, losing by two points. In Game 4, they pulled out a series-tying win.

At home, the Celtics may have gotten too comfortable. This time, it was Boston who held a 14-point lead in the fourth quarter. The Bucks outworked and outhustled the favored Celtics on their homecourt and managed to stun the sold-out crowd with the improbable three-point win.

The Celtics may say they aren’t mentally shaken by this loss, but they have to be. They gave the game away, and now Milwaukee can close out the series at home Friday night.

“Of course, we’re gonna be down. Guys are going to be (upset) about the outcome. We outplayed them for 3½ quarters,” Celtics coach Ime Udoka said, per ESPN. “We talked about showing our resolve, and we made it tougher on ourselves now. It’ll make it sweeter when we bounce back. But we gave up a golden opportunity tonight.”

The Boston Celtics went back to their old ways

This felt like a late-November Celtics game. Back then, the Celtics hadn’t found themselves yet. They were playing under a new coach in a new system, and there was a lot of doubt with the team.

Marcus Smart called out Jayson Tatum and Jaylen Brown for not passing the ball enough. Udoka often questioned the team’s effort. Boston blew several big leads late in games.

Since late January, however, the Celtics have been a much different team. They ended the regular season by winning 26 of their last 32 games. They swept Kyrie Irving and Kevin Durant in the first round. Boston had the defending champion Bucks on the ropes in Game 5 but went back to their old ways.

Instead of stepping on the throat of the Bucks with the 14-point lead in the fourth, they cruised. They didn’t box out. Tatum complained about calls instead of getting back on defense. They got careless with the ball. It came back to bite them.

“If we box out we win that game,” Smart said. “They’re the defending champs. They made some championship plays. And now we’ve got to bounce back.”

If only they thought that during the game.

The Celtics have a tough road ahead

The Celtics now have to win two in a row, something that hasn’t happened in the series. Winning in Milwaukee with momentum clearly on the Bucks’ side is a tough task.

The Celtics did it in Game 4 and nearly did it in Game 3. They’ll tell you they can do it in Game 6, but they need to be the 2022 Celtics and not the 2021 team.

Tatum needs to get off to a quick start. He hasn’t done that. He’s struggled from long range and needs to take it to the hold. When he does, he needs to stop complaining every time he misses a shot. Tatum needs to be the leader of this team, and he hasn’t been.

Game 6 is the perfect opportunity for Tatum and Brown to strut their stuff. Brown has been in the NBA for six years and Tatum five. They are no longer the young guys with the promising future. It’s their time to lead.

“The biggest challenge of the year,” Brown said of Game 6, per CBS Sports. “Mentally, physically, emotionally, it puts a challenge on every component. So, we’ve gotta regroup and get our spirit to the point where we can go in and get a victory in Milwaukee.”

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