The Wales midfielder hopes to be back in action for West Ham over Christmas.
On Grant, Collison told Soccer AM: "The new manager seems good. He's quite friendly and comes over and says 'Hello'. At the moment I'm in getting physio every day and it's nice being in and around the boys and being in the mix.
"I think they've all reacted really well to him. He's obviously bringing in his own ideas and it's up to us to start picking up a few points I think.
"Obviously it's not a great start to the season and nobody wants to start like that, but the new manager has come in and he's got his own ideas of how he wants to play and maybe it's going to take a little while to adapt.
"It's only early doors and we've got a nice easy one next week against Chelsea so hopefully we'll pick up some points there."