Following the departures of Chris Humphrey, Darren Randolph and Henrik Ojamaa, James McFadden, Michael Higdon and Tom Hateley are also expected to follow the trio to the exit.
McCall guided his side to an impressive second place finish last season, but he now finds himself left in the dark over the futures of a number of key players.
"It's a question of waiting to see who reports on Thursday," he told The Daily Record.
"I'm not sure if Higgy or Tom will be back and our chief executive will be speaking to Faddy so we'll see what happens.
"However, these players have all been made offers and I won't wait weeks for them to decide.
"We're happy to have signed Iain Vigurs and Paul Lawson, but there's no point handing out deals just to make up the numbers."
McCall also admitted that he may look towards the loan market as Motherwell aim to build on last season's success.
"I've gone to England in the past to sign the likes of Nicky and Simon Ramsden but it's harder to persuade players to come to the SPL now," he said.
"The loan route may be our best bet. We want to try to improve on what we did last season but we know that will be nearly impossible."