LAKE BUENA VISTA, Fla. -- After the Boston Celtics shot the Toronto Raptors back into their Eastern Conference semifinal series Saturday night, 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 through the first three games of the series, but he shot just 1-for-6 from 3-point range Saturday night -- part of a disastrous teamwide performance from behind the arc, as the Celtics went 7-for-35 from behind the arc.

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 exactly a half-second away from going up 3-0 in this series two nights ago after Walker's sublime no-look bounce pass to Daniel Theis for a dunk with .5 remaining on the clock. But then Kyle Lowry hit OG Anunoby with an even better pass to set up the game-winning 3-pointer, allowing Toronto to live to fight another day.

The Raptors then took advantage of that opportunity in Game 4, evening the series by stymying Boston's previously dynamic offensive attack. It was the first time since Gordon Hayward's injury in Game 1 of the Celtics' first-round sweep of the Philadelphia 76ers that the team truly felt the impact of his absence, as the Celtics could've used another shot creator -- and shotmaker -- 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 themselves 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 night, the Celtics managed to remain within striking distance thanks to an impressive defensive performance of their own. In what is becoming a trend in this series, both teams made it exceedingly difficult on the other all night, which kept the game from ever feeling like it was out of hand.

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

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

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

"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."