McCall did not name those who have told them of their intention to leave - in case they have a change of heart - but he is hopeful they will spring some surprises in persuading some to stay.
Most of the experienced Motherwell players - Darren Randolph, Tom Hateley, Simon Ramsden, Nicky Law, Chris Humphrey, Michael Higdon, James McFadden, Steven Saunders and Omar Daley - are coming to the end of their contracts.
McCall has a "rough idea" who will stay and the completion of his own two-year deal and their secured top-six place in the Clydesdale Bank Premier League will prompt more negotiations after young players such as Stuart Carswell and Bob McHugh signed up in recent weeks.
McCall, whose side face Dundee at Dens Park on Saturday, said: "I'll be confident that we'll keep a few but likewise I know that we'll lose a couple. That can go for every club in the SPL and I'm sure it will.
"We'll try to make inroads in the next few weeks on the ones we think we can offer terms to.
"Maybe some players will wait and see but we will put a time limit on it. We need to know where we are going. We will be at least able to offer contracts in the next few weeks.
"We managed to keep Jenno (Steve Jennings) a year longer than many would have thought and hopefully we will manage to keep one or two longer than people think. We will lose a couple of players who have given the club great service and we will wish them well, but we have to focus on the here and now."