Marquise Brown has been slower to recover from surgery than initially anticipated. Even so, there's been optimism throughout the offseason that the rookie wide receiver would be ready to take field for training camp. But with the Baltimore Ravens' first official practice of the 2019 season right around the corner, Brown still hasn't been given a clean bill of health – and there's no telling when he'll get it.

The Ravens placed Brown on the active/non-football injury list on Thursday, indicating he would be unavailable for the start of training camp.

Baltimore selected the Oklahoma product with the No. 25 overall pick of the NFL Draft. He had 75 catches for 1,318 yards and 10 touchdowns for Oklahoma last season, emerging as the best big-play threat in college football.

Brown suffered a dreaded Lisfranc injury to his right foot in the Big XII championship game, undergoing surgery in February. He was unable to participate in the NFL Draft combine and the Sooners' Pro Day as a result, but boasted he would have broken the record for the 40-yard dash, 4.22 seconds, held by the Cincinnati Bengals' John Ross.

Interestingly, Brown participated in drills at the Ravens minicamp in May, but wasn't cleared by doctors two months later, suggesting he might have suffered a setback. NFL Network's Ian Rapoport reported on Thursday that he's expected to practice within a few weeks.

Baltimore opens training camp on July 25. Even if Brown is healthy enough to return to action between now and the season-opener on September 8, he'll have missed valuable time on the practice field with quarterback Lamar Jackson and his teammates.