Atlanta Hawks guard Lou Williams said he found out one hour before tipoff that he would be starting a playoff game for the first time in his 16-year NBA career.

The 34-year-old Williams learned of the assignment at the same time he was told that his teammate Trae Young would sit out Game 4 with a foot injury.

But Williams was more than up to the task and contributed 21 points and eight assists as Atlanta posted a 110-88 victory over the visiting Milwaukee Bucks on Tuesday night to even the Eastern Conference finals at two games apiece.

Williams' big effort fueled the fifth-seeded Hawks on a night in which the third-seeded Bucks lost their own star.

Two-time NBA MVP Giannis Antetokounmpo hyperextended his left knee in the third quarter and didn't return.

Antetokounmpo got injured when he leaped to defend an alley-oop pass to Hawks big man Clint Capela.

The 26-year-old Greek player had 14 points and eight rebounds in 24 minutes before exiting with seven minutes and 14 seconds left in the third period.

Then, Antetokounmpo was helped off the floor by his brother Thanasis after getting hurt.

"We'll take everything as it comes. We'll evaluate it. We've got a heck of a team, a heck of a roster," Bucks coach Mike Budenholzer said afterward.