The Fir Park side have 10 players whose contracts expire in the summer.
But financial constraints mean McCall cannot finalise his first-team budget for next term until he knows exactly how much the club will earn in prize money for this year`s Clydesdale Bank Premier League campaign.
Well - who lie currently second in the SPL - need just three wins to secure their place in the top half for the post-split run-in.
Now McCall has told those players whose deals lapse at the end of May - Michael Higdon, Darren Randolph, Tom Hateley, Steven Saunders, Nicky Law, Chris Humphrey, Omar Daley, Robert McHugh, Simon Ramsden and James McFadden - to secure the necessary points as soon as possible so he can open negotiations.
The manager - who hopes to finalise a new deal of his own early next week - said: "I`ve spoken to the agents and got a heads up for where most people are going to be.
"But until we get to the top six, we can`t look to offer deals because we don`t want to offer people contracts that we can`t afford.
"It`s where we are with the finances of the game. There are no guarantees where you are going to be.
"I look to last season when Keith Lasley and Stevie Hammell had to be persuaded to stay over a shandy when we were away at the end of the season.
"It`s not ideal when it goes to that stage but at least then you are not giving false promises."