They are holding their collective breath in Milwaukee.

You could almost hear the gasps all the way back in Atlanta.

Bucks star Giannis Antetokounmpo left Game 4 of the Eastern Conference finals against the Hawks with a hyperextended left knee suffered in the third quarter Tuesday at State Farm Arena. The two-time NBA MVP was unable to return. The Hawks extended an already double-digit lead once Antetokounmpo left and went on to a 110-88 victory. The Hawks won convincingly with their own star, Trae Young, unable to play due to a bone bruise in his right foot. The best-of-seven series is tied 2-2 with Game 5 in Milwaukee on Thursday.

Antetokounmpo was injured as he tried to block a lob pass from Lou Williams to Clint Capela, who dunked the ball. Both landed awkwardly, but the left knee of Antetokounmpo buckled. He left with 7:14 remaining in the quarter with the Hawks leading by 10 points. They went on a 15-0 run following the injury to put away the game they never trailed.

Bucks coach Mike Budenholzer had no further update on Antetokounmpo following the game. It’s likely he will undergo tests when the team returns to Milwaukee.

“Obviously, Giannis is a big part of our soul, our fiber,” Budenholzer said. “I’m sure there is the human element, the concern, the care for him is real.”

Antetokounmpo left the court following the injury. He returned to the bench but later returned to the locker room and the Bucks announced he would not return. Budenholzer said Antetokounmpo addressed the team in the locker room following the loss. Teammate Jrue Holiday said the comments were all positive.

“We’ll take everything as it comes,” Budenholzer said. “We have a heck of a team, a heck of a roster. The guys will be ready to compete and play. That’s what it’s about. We got a Game 5.”

Antetokounmpo finished with 14 points on 7 of 10 shooting. The Hawks held him in check early in the game. He was held scoreless in the first quarter and to six points in the first half. He got going in the third quarter before the injury ended his night and left a pall over the team.

In 14 postseason games before Tuesday, Antetokounmpo averaged 29.2 points, 13 rebounds and 5.4 assists in 38.3 minutes.

Clearly, it would be a major loss for the Bucks if Antetokounmpo is limited or can’t finish the series.

“It’s not good,” Bucks’ P.J. Tucker said. “But this is the Eastern Conference finals. There is no excuse. It doesn’t matter whoever is playing, not playing. They’ve got guys hurt. Everybody is hurt. Everybody is banged up. Everybody is injured. You’ve got to fight through it. …

“It’s not good losing anybody on your team. You lose your best player, it stinks.”

The Bucks gave credit to the Hawks, who stepped up with their own star watching in street clothes. The Hawks had six players score in double figures, including Lou Williams with a game-high 21 points starting in place of Young.

“They had a lot of guys play well tonight, for really the whole game,” Budenholzer said. “Credit to Atlanta. They played well from the start. They played well coming off the (Trae Young) injury. We’ve got to be better on both ends. Our group will gather. The character of our group will come through. We are going home. It’s 2-2. We are going back to Milwaukee.”

The injury watch is on.