There was a slight spark after the interval but it hardly caught fire.
Saints took charge for a 15-minute spell and Trevor Carson had to paw out a David Wotherspoon drive moments after clutching Scott Tanser’s free-kick.
Cedric Kipre saw yellow for crudely halting a promising Chris Kane run with Wotherspoon firing the free-kick narrowly past.
Well posed more of a threat as well and Main wriggled free of his man before curling an effort wide and Gael Bigirimana’s free-kick was awkwardly spilled by Alan Mannus.
Richard Foster lashed a volley high in to the Perthshire sky as the home side struggled to carve out a winner.
All of Motherwell’s focus now turns to their third trip to Hampden this season on Saturday.