Harlequins boss Conor O'Shea revealed his regret at having to sell Sam Smith after the wing scored a try in Saturday's win over Worcester.
O'Shea said the salary cap was the only reason he decided to sell Smith, who ironically is joining the Warriors.
He also also set up a try for new centre Harry Sloan as Quins struck back after trailing 13-0 to claim a 21-20 victory.
"We're sorry to see him go, but the salary cap is the salary cap," said O'Shea.
"We thought Worcester were picking on him - they've signed him but they were kicking all the balls to him - but Smithy's just an outstanding pro.
"He's a try-scorer, always has been. He'll be a good acquisition for them."
Harlequins were without England stalwarts Chris Robshaw, Mike Brown, Danny Care and Joe Marler as well as several other players who are on the injury list.
"We knew we would have to fight tooth and nail through this international period," added O'Shea.
"It's an incredible injury list and it's tough.
"We have played four games in this window with so many players unavailable, and we've won three and got a bonus point.
"We have inadvertently blooded some outstanding young talent which should stand us in good stead for the future, with players like Kyle Sinckler and another 20-year-old Harry Sloan, who has been out injured this season."
Worcester's one-point loss was their 16th on the trot but despite the result their director of rugby Dean Ryan hailed his troops.
"It's been a pretty raw week for us. I was hoping we could get the right response, and we did.
"We are struggling physically to cope with such a small group. You can see when we start rolling the bench that things get a little bit ragged, and we couldn't really stem the flow.
"We're still fighting like mad and still feel we can get something in the back pocket before we go to the north-east (to face second-bottom Newcastle).
"There isn't any lack of work-rate from this group.
"This club just has to make sure that remains central to everything it does and then it expands its squad. Then we can grow the club in the way that we play."