Gus Poyet wrote an open letter to the Sunderland support in midweek, appealing for unity between the fans and the team, but the Uruguayan's prospects will not have been helped by another stodgy display.
Although failing to create clear-cut chances, Sunderland should have been ahead on the stroke of half time when Adam Johnson stole in to tuck home from close-range, but the goal was erroneously ruled out by the officials.
They have now only claimed one victory from their last nine league fixtures, with Saturday's goalless stalemate their 13th of the campaign.
Sunderland made five changes to the side that was dumped out of the FA Cup by Bradford City last time out, with Poyet drafting Lee Cattermole – out since December with niggling groin injuries – straight back into the starting line-up.
Despite Sunderland's protestations, Lescott escaped with just a booking, while Sebastian Larsson fired into the side-netting from the resulting free-kick.
Poyet's side continued to press West Brom, with the visitors unable to get the ball into the feet of in-form striker Brown Ideye.
However Sunderland lacked the quality to make their possession count against a typically organised Pulis defence, though Jermain Defoe did go close before John O'Shea headed wide from a whipped Larsson free-kick.
Johnson had the ball in the back of the net in the 45th minute when, after latching onto Vergini's cross at the back post, but the strike was incorrectly disallowed for offside.
Foster had to be alert again a minute later to palm away Larsson's stinging drive before the break, but Vergini could not work the England man from close range 15 minutes into the second half unmarked from Larsson's corner.
