Goals by Teddy Sheringham and Hayden Mullins put West Ham on the way to their first victory since the opening day of the season to lift the pressure on the Hammers boss, whose tricky tenure in the Upton Park hot-seat had been shortening by the minute.
And although David Bentley's late tap-in set up a frantic finale that left the home fans on the edge of their seats, that Rovers effort came far too late to deny United the win that ended an excruciating eight-game losing sequence.
Both teams came into this match after enduring midweek Carling Cup exits but the Hammers' dour defeat at Chesterfield had left Pardew in dire straits.
Indeed, no West Ham United side had ever lost eight consecutive games in the same season until then and although they recorded nine successive reverses back in 1932, that sequence came across the end of one campaign and the start of another.
Certainly, it was a record that the under-fire Pardew did not want to equal and following his side's Saltergate shambles, the Hammers boss made a quadruple switch, asking the veteran Sheringham to lead his attack, while Jonathan Spector, Matthew Etherington and Yossi Benayoun also returned to the fold.
Mark Hughes, who saw his side lose to champions Chelsea on Wednesday evening, made five changes as Tugay, Andre Ooijer, Sergio Peter, Michael Gray and Jason Roberts each returned.
West Ham may have kicked off in 19th place and without a clean sheet all season, but their long-suffering fans made it clear that the boss was not to blame as they serenaded him with a welcome chorus of 'One Alan Pardew' at the kick-off.
And although they kept the decibel level high during the opening quarter-hour they had little to cheer apart from Mullins' low 18-yarder that was comfortably taken by Brad Friedel and a Nigel Reo-Coker effort that flew wide of the keeper's right-hand post.
But midway through the half, Sheringham showed that there is no substitute for experience when he laid the ball wide to partner Bobby Zamora, who cut it back to Benayoun. And when the Israeli delivered an inch-perfect cross to the near post, the unmarked 40-year-old powered Hammers ahead with a ten-yard header.
Having just fallen behind, Blackburn's afternoon went from bad to worse as the fleeing Bentley was tripped by the consequently-booked George McCartney, before Roberts was stretchered away after falling awkwardly following Spector's touchline tackle.
Early in the second period, Roberts' replacement Francis Jeffers drilled narrowly wide, before one-time Hammers target Benni McCarthy forced Robert Green into his first serious piece of work with a vicious low 18-yard snapshot.
As the hour-mark approached, the South African threatened again, but this time referee Alan Wiley ruled out his coolly-taken goal for a foul on Anton Ferdinand.
Midway through the second half Zurab Khizanishvili nodded over Peter's well-flighted corner and as Pardew uneasily paced his technical zone, he realised it was Rovers who looked most likely to find the net.
Certainly when another Peter corner fell to the unmarked Lucas Neill at the far post, that leveller looked odds-on but the Australian's point-blank shot somehow cannoned off the well-placed Green.
While Rovers held their heads in disbelief, Zamora burst clear in a classic counter-attack but with just Friedel to beat, his touch deserted him and the relieved Rovers keeper denied him with his knees.
But just when Blackburn thought they could still salvage something from the contest, Etherington's in-swinging 80th-minute corner found its way to Mullins in the six-yard box and he slammed home the Hammers' second.
There was still time for the impressive Bentley to gobble up the rebound after McCarthy's stoppage-time shot was parried by the hitherto faultless Green but it was too late to deny Pardew a match-winning, job-saving victory that finally brought the smiles back to the East End.