Kevin C. Cox/Getty ImagesGiannis Antetokounmpo, who was previously listed as questionable for Game 5 in the Eastern Conference Finals is now officially out.The Bucks announced that the two-time NBA MVP would not be able to face the Atlanta Hawks due to the hyperextended left leg he sustained in Game 4.The Bucks placed Antetokounmpo in doubt with a knee injury on Wednesday.According to ESPN's Adrian Wojnarowski, Zach Lowe and ESPN, Antetokounmpo was not injured by a MRI and his ligaments were healthy.It happened midway through Game 4, when Milwaukee lost 110-88 to Clint Capela. Antetokounmpo tried to contest Clint Capela's alley-oop pass, but his left knee buckled as he landed.It is not clear how long Antetokounmpo may be absent beyond Thursday's home match at Fiserv Forum. Five-time All-Star Antetokounmpo is averaging 28.2 point, 12.7 rebounds, and 5.2 assists per contest with a 55.1 field-goal rate in 15 games this postseason.With Antetokounmpo out of action, Bucks coach Mike Budenholzer will likely turn to Bobby Portis to be his primary power forward. In 21 minutes, the 26-year old scored seven points with 3-of-9 shooting during Game 4.Atlanta will host Milwaukee in Game 5 of Eastern Conference Finals at 8:30 p.m. on Thursday. ET. ET.