The 24-year-old is one of a number of players out of contract at the end of the current campaign, including 16-goal Michael Higdon.
But with gaffer McCall still to sign a new deal, the midfielder has urged Well bosses to nail down the influential manager to avoid the break up of the current squad.
Law said: "It looks like the gaffer may sign up for another season or so, but until he does then it is an issue.
"Stuart McCall is just a top man and you look at the job he has done at the club in his two-and-a-half years and it is vital that he is signed up.
"It is a pleasure to work under him, my own game has developed at a faster pace because of that.
"If the board could get Stuart signed up soon it would sent out a positive message.
"There are so many of us out of contract at once that it would certainly play a part in getting people to sign on again."
While Law is candid about the importance of getting McCall to commit, he also admits that a successful outcome in Well's Euro campaign will be another huge factor .
He said: "The experience of playing in both the Champions League qualifiers and the Europa League qualifiers was fantastic.
"How many players at clubs like Motherwell can boast of that?
"Once you have had that type of experience you definitely get greedy and want more.
"It would be great if we could stay together as a squad for another crack at Europe."
Well are not back in action until next Tuesday when they face Dundee United at Fir Park, and Law is hungry for revenge.
He said: "Our last loss at home was against them and it still rankles.
"We are on a good run at home and the win over St Johnstone took that unbeaten sequence to six.
"There wasn't much wrong with our home form during the first-half apart from the end result at times.
"On Sunday we proved that we have found the way to win when we are not at our best."