Defending champions Milwaukee Bucks pushed Boston to the brink of NBA playoff elimination after overturning a double-digit fourth-quarter deficit to beat the Celtics 110-107 on Wednesday.
The Golden State Warriors, in the meanwhile, were missing in action as the Memphis Grizzlies stayed alive with a 134-95 drubbing of the visitors.
The Grizzlies, facing elimination and playing without injured All-Star guard Ja Morant, weren't about to go out on their home floor.
They raced to a 38-28 first-quarter lead and never trailed as they cut the deficit in their best-of-seven Western Conference series to 3-2, sending it back to San Francisco on Friday.
"We just stuck to the game plan," said Grizzlies forward Jaren Jackson Jr, one of three Memphis players with 21 points.
"We knew what was at stake. We didn't change anything though, we just calmed down, looked at the film, understood what we had to take away from the last game and just went out there and executed."
Desmond Bane and Tyus Jones also scored 21 for the Grizzlies, who had seven players score in double figures in the wire-to-wire win.
Klay Thompson led the Warriors with 19 points.
Jonathan Kuminga added 17 and superstar Stephen Curry scored 14 on four-of-10 shooting for the Warriors, who coughed up 22 turnovers leading to 29 Grizzlies points.
"It was awful, embarrassing," Thompson said. "We all had the mindset we were going to close it out tonight, but sometimes basketball is an inexact science and we played like a shell of ourselves."
The Grizzlies outrebounded the Warriors 55-37 and led them 24-5 in second-chance points.
Up by as many as 55 late in the third quarter, the Grizzlies were flirting with NBA history, with the largest margin ever in the playoffs – 58 points.
It was a massive comedown for the Warriors, who played their second straight game with head coach Steve Kerr sidelined by COVID-19.
The third quarter hadn't ended when stars Curry, Thompson and Draymond Green were pulled by acting coach Mike Brown.
In contrast, it came down to the wire in Boston, where Giannis Antetokounmpo scored 40 points and Bobby Portis and Jrue Holiday came up big late as the reigning NBA champion Bucks rallied to take a 3-2 lead in their Eastern Conference series.
Reserve forward Portis put back Antetokounmpo's missed free throw with 11.4 seconds remaining to give the Bucks a 108-107 lead.
Jrue Holiday plucked an attempted shot by Marcus Smart from the air with 8.1 seconds remaining before teammate Pat Connaughton added a pair of free throws to seal the comeback for a Bucks team that trailed by 14 early in the fourth quarter.
Milwaukee took a 3-2 lead in the best-of-seven Eastern Conference series and will have a chance to close it out when they host game six on Friday.
Jayson Tatum and Jaylen Brown combined for 60 points for the Celtics, who took control with a 28-19 second quarter that saw them take a 54-47 halftime lead.
They maintained the edge throughout the third, but the Bucks didn't back down.
Connaughton's 3-pointer with 7:34 to play cut the deficit to 98-90. Jrue Holiday added a jump shot to cut the margin to 101-99.
Three-pointers from Antetokounmpo and Holiday knotted the score at 105-105 with 43.2 seconds left, setting the stage for a dramatic finish.
"Obviously, in Boston, you're down 14 in the fourth quarter, people would say everything's against us. But we come together," Holiday said. "We live and die like that."
Holiday added 24 points for Milwaukee while Portis scored 14 and Connaughton 13 off the bench.
"We just didn't do what we were supposed to do," said Smart, who scored 15 points for the Celtics. "We didn't execute when we were supposed to, and when it mattered the most, they did."
Celtics coach Ime Udoka said it was a bitter defeat after "we outplayed them for three and a half quarters.
"We talked about showing our resolve, and we made it tougher on ourselves now," Udoka said. We gave up a golden opportunity tonight."