Hooker George McGuigan left Newcastle Falcons earlier this week to join Gallagher Premiership rivals, Gloucester.
The 29-year-old made 165 appearances during two spells with the Falcons, scoring a total of 48 tries.
Walder said: “The board are in charge of all recruitment and retention and they felt that was the best decision for the club and it happened very quickly.
“There is nothing you can do and you just have to get on with it. It is never good to see your best players leave but my job as head coach is to coach the players I have got and get the best out of them. The board take those decisions and I am looking forward to giving it a shot against Cardiff. Jamie has signed a new contract and has been involved with England and we are excited to see him kick on.
“We have always cut our cloth accordingly and what has gone with Worcester and Wasps has got everybody treading on eggshells a little bit and I cannot speak for other people’s perceptions (of Falcons). We get on and do our job with what we have got to help the club moving forward. My job is to deal with the rugby side and develop players from within. It’s a part of the job I enjoy.
“George is a great player but Jamie has the potential to be a very, very good player and we are excited about what he can do and he will get more of a chance now. We also have a couple of young guys coming through who will be able to step up. We have to get on with it and a couple of them will get a chance on Saturday.”
PREMIERSHIP CLUBS RANKED BY TOTAL DEBT:
#13. Exeter Chiefs – £13m
#12. Gloucester – £27m
#11. Northampton Saints £26.5m
#10. Worcester Warriors – £26.5m
