The phrase "to rebuild the club" means fixing or improving a sports team or social organization by making necessary changes and improvements. Full definition
I agree — the sooner we start rebuilding this club the better. (justarsenal.com)
It is amazing that we have to rebuild this club yet again after all these efforts we put in in the last 10 years. (justarsenal.com)
However, I don't believe in rebuilding a club without addressing the position of manager first, regardless whether he's solely responsible for player recruitment or works with a committee. (7amkickoff.com)