Kevin Blackwell admits Sheffield United will struggle to find a replacement for Simon Walton because they will continue to pay the loan player's wages.
The 22-year-old midfielder was just 15 minutes into his Blades debut at Mansfield on Saturday after signing on a season-long loan from Plymouth when he suffered a cruciate knee ligament injury, which will rule him out for a year.
United are in discussions with Plymouth over Walton's rehabilitation but the Blades have said they will honour the terms of the deal and pay his wages for the season.
Walton is far from being among the club's top earners and the former Leeds trainee was so determined to kick-start his career in the Championship it is thought he also forfeited any appearance or goal bonuses.
However, United's decision to honour his contract will still hinder Blackwell's bid to bring in reinforcements ahead of the new season.
"It doesn't help us going back into the market and getting someone else in," the Blades boss told the Yorkshire Post.
"We're effectively paying money on a player who cannot play for you, cannot help you, so that's a blow.
"I don't know yet whether it will be another loan player or not. I didn't want to have too many loans but I was prepared to take one or two, and Simon covered me in more than one position and it meant I didn't have to go looking at specific right-backs.
"I knew that having got the main targets in I'd got cover and back-up, but that back-up's now wiped away so we will have to think again.
"We knew this season we wouldn't be massive in numbers and he had the ability to play two or three positions.
"I'm afraid for us it's one step forward, two steps back - that's the way the game's going for us."