LAKE BUENA VISTA, Fla. — After the Boston Celtics shot the Toronto Raptors back into their Eastern Conference semifinal series on Saturday, Celtics star Kemba Walker placed the blame on his shoulders.

“I got to be more aggressive,” Walker said after finishing with 15 points on 4-for-9 shooting with eight assists in Toronto’s 100-93 win in Game 4, which tied the series at two games apiece. “I wasn’t aggressive enough.

“That’s unacceptable on my behalf, to be honest. There’s no way I can just be taking nine shots. That’s unacceptable.”

Not only did Walker shoot just nine times — after getting virtually wherever he wanted on the court in the first three games of the series — but he also shot 1-for-6 from 3-point range Saturday as part of a disastrous team performance from beyond the arc. The Celtics went 7-for-35 from 3-point range. That included a dismal 5-for-22 on uncontested 3-pointers, per ESPN Stats & Information research.

Toronto, on the other hand, went 6-for-8 on uncontested looks.

“Honestly, man, I thought we had great looks,” Walker said. “I thought we had great looks throughout the whole game.

“We just really missed. We missed a lot of open ones that we know we can make. Like I said, we gotta make them. We have to make shots. When guys get shots, when guys are open, we gotta knock them shots down.

“We’ll do better. We’ll do better.”

Boston was a half-second away from going up 3-0 in this series on Thursday, after Walker’s sublime no-look bounce pass to Daniel Theis for a dunk with 0.5 seconds remaining on the clock. But then Kyle Lowry hit OG Anunoby with an even better pass to set up the game-winning 3-pointer.

The Raptors then took advantage in Game 4, evening the series by stymying Boston’s previously dynamic offensive attack. It marked the first time since Gordon Hayward’s injury in Game 1 of the Celtics’ first-round sweep of the Philadelphia 76ers that the team felt the impact of his absence, as the Celtics could’ve used another shot-creator — and shot-maker — on a night when they couldn’t get anything to go through the hoop.

A big part of that was guard Jaylen Brown, who finished 4-for-18 — including 2-for-11 from 3-point range — and was one of several Celtics who found clean looks that wouldn’t go down.

“I just missed some open shots,” Brown said. “I’m a good shooter. I’ve just got to make them. It’s make-or-break time, 2-2. The series is tied up. We didn’t play that well. I didn’t play that well. We got to bounce back and be ready to fight.

“That’s what it comes down to: fight. We have to be ready to fight for our lives next game and keep playing good basketball. Open shots just didn’t go down. Tough night.”

Even with their off shooting, the Celtics managed to remain within striking distance, thanks to an impressive defensive performance. In what is becoming a trend in this series, each team made it exceedingly difficult on the other, which kept the game from ever feeling like it was out of hand.

The difference was that although Toronto finished the game shooting below 40% from the field, the Raptors managed to go 17-for-44 on 3-pointers.

Brown, Walker and Jayson Tatum, however, said there was another factor: The Raptors simply played harder than the Celtics.

All of them said that will have to change in Game 5 if Boston wants to regain control of a series that it nearly had its hands around in Game 3 — and that has become a toss-up.

“It’s tough, man,” Walker said. “Obviously, we didn’t want to come out that way, but it just happened. We’ve just got to clean it up. We’ve got to find a way, man. We’ve got to be better. I have to be better. I have to find a way to get my teammates at a higher intensity, and I will. I’m going to try my best to bring the best out of these guys.

“Nobody ever said it was going to be easy. We know how the playoffs is, and these are the defending champs. These guys have been through it. These guys have been through it. They’ve been through the fight before. They’ve been down before. They know what it takes.

“But I can’t stress enough how much we just have to be better.”