While most of the talk has been on Coleman's future as manager, with negotiations over a new contract understood to be progressing positively, the former international defender has been dealing with changes to his squad.
Goalkeeper Boaz Myhill along with midfielders David Vaughan and Andrew Crofts have all pulled out but, at the moment, Coleman has opted to only bring Collison back into the squad to face Finland in a friendly at the weekend.
Myhill was the first to withdraw as he will remain with his club West Brom to have treatment on an Achilles problem and ligament damage to his left thumb.
"Personally I am going to need treatment on a couple of injuries I've picked up in recent weeks and need to get over," the 31-year-old told www.wba.co.uk.
"I've not trained for a while and I'm glad for the rest because it means I can do some work in the gym with the physios so the break has come at a good time for me.
"I was really struggling last week and I'm grateful to the medical staff for the help they've given me to get on the pitch."
Sunderland's David Vaughan, currently on loan at Nottingham Forest, then injured a hamstring in training and was ruled out of the match while Brighton's Crofts also withdrew due to an on-going groin problem.
Despite the upcoming friendly, speculation continues about the future of Coleman, whose contract is due to expire after the match.
Press Association Sport understands discussions with the Football Association of Wales over a new deal to take the current boss through to the end of the Euro 2016 qualifying campaign have been constructive.
It is understood Coleman has indicated to FAW chiefs he wants to take Wales forward, and they believe he represents a safe pair of hands.
However, any expected agreement is not likely to be forthcoming until later in the week.