Khris Middleton will reportedly miss the Milwaukee Bucks' season opener on Wednesday against the Philadelphia 76ers, according to ESPN's Shams Charania.

Middleton underwent a pair of ankle surgeries — arthroscopic clean-ups — in the offseason.

"Day-to-day and we'll know as [him returning] gets closer," Bucks head coach Doc Rivers said on Saturday "Each day he doesn't do anything obviously we get a little more concerned for sure."

The team was hopeful the three-time All-Star forward would be ready for the start of the season, but considering his value to the Bucks — 15.1 points, 4.7 rebounds and 5.3 assists per game last season — they are taking a cautious approach to his rehab.

"We're not gonna just say 'all right,'" Rivers said. "If he doesn't go [opening night] then we'll wait 'til the next one. I'm really not concerned. It's a long season. Do I think he'll play in Game 1? I'm hoping. Still pretty positive there. If he doesn't, does it ruin my year? No. I think he'll be healthy soon and we'll have him a lot. So I'm not that concerned by it."