Brooklyn Nets stars Kyrie Irving and James Harden will both miss Game 5 of the Eastern Conference semi-finals against the Milwaukee Bucks due to injury.

Irving sprained his right ankle in the Nets' 107-96 loss in Game 4 on Sunday and underwent an MRI which confirmed he would not be available for Tuesday's clash, with the NBA playoff series in tied at 2-2.

Nets guard Irving joins former MVP Harden on the sidelines, with the latter still absence because of a hamstring he re-injured in Game 1.

Brooklyn head coach Steve Nash said the length of Irving's absence remains unknown.

"I have to wait and see how it progresses, I think," Nash said.

"And then the experts would have to wait and see how it progresses and give you a clearer picture on what the window would be for his return."

Nash added that Harden was "working out right now" but was unclear on his return to play timeframe.

The second-seeded Nets – eyeing their maiden championship – have battled injuries throughout the 2020-21 campaign, with Harden missing 21 games late in the regular season due to his troublesome hamstring.

"It's tough to lose great players but we've lost guys all season," Nash said. "If there's any silver linings, it's that we've continued to win games regardless of who's been available.

"We've been able to adapt on the fly which is difficult to do sometimes. That's something we have some experience with. We should have some comfort and belief."

The absence of two-thirds of the 'Big Three' puts a heavy burden on Kevin Durant, although Nash insisted it was not just about him.

"This does not fall on Kevin, this falls on the Nets," Nash said. "We've got to find a way together to play great basketball on both ends of the floor. We've proven we can do it.

"We try to stick to our principles and fundamentals, which is connectivity, competitive spirit, embracing the opportunity and playing together as a team."