Southampton youngster Diamond Edwards has been ruled out for the rest of the season.
The 19-year-old attacker suffered an ACL injury last month, which has curtailed his rise as a footballer.
The forward was set for his breakout season with Ralph Hasenhuttl's team.
He was part of their pre-season tour of Austria, and was set to play a significant role with the Under-21s as well.
“Unfortunately, we've lost Diamond for the season," Dave Horseman, the club's B team head coach, told Daily Echo.
“He's done his ACL away at Leeds. We've been a bit unlucky. What you're seeing here what it does do, every negative has a positive. It means little Sam (Amo-Ameyaw), who I think we can all see the insights team have done a magnificent job getting him in.
“So there is turnover, but there should be turnover. That should be the under-21s - that's our job is to get them up into the first team and out on loan and then move on to the next lot," he continued.
“So we always go after it as a team, but it's not. There are 11 players on 11 different journeys there and we have to manage it. That's the uniqueness of an under-21s team."