The defender put the only goal of the contest beyond goalkeeper Paul Robinson with less than four minutes remaining to send Wigan safely clear of the third and final relegation spot with one fixture to spare.
Blackburn, meanwhile, now join Wolves as a doomed entity and enraged home fans ran onto the pitch at the final whistle as manager Steve Kean was escorted through the tunnel.
The invasion was far from the only extra-curricular happening in Lancashire, as a chicken in a Blackburn cape was sent onto the pitch after the opening few minutes, while one spectator began the second by entering the field of play to hurl his season ticket to the ground.
For a game with so much on the line for both clubs – especially the hosts – the first half was one of little action courtesy of awful rain-soaked conditions and the show-stealing appearance of the ‘Ewood Chicken’.
Rovers adopted a 4-3-3 with Kean hoping to take the game to the side’s neighbours, but the majority of the sparing opening chances came the way of buoyant Wigan.
Franco di Santo forced a fine parry from Paul Robinson after nine minutes while the majority of those in attendance remained distracted as a chicken clad in a Rovers cape was taken from the pitch by a steward.
Anthony Modeste may have had Papiss Cisse’s incredible goal for Newcastle last week on his mind when he unleashed a wild volley from Yakubu’s chest down two minutes later, the effort appearing to head well off-target before curling its way within inches of the crossbar.
Di Santo, who made 23 league appearances on loan for Blackburn in 2009-10, sent in a superb cross from the right with ten minutes remaining in the first half which Victor Moses should have headed over the goal line, but could only nod away from goal under pressure.
The game opened up somewhat following the interval, perhaps with the implications of each possible result growing on both sets of players, and the hosts were first to take the initiative.
A corner on 53 minutes was headed across goal where Yakubu had his eventual shot from a few yards out cleared off the line by Jean Beausejour.
Six minutes later and a goalmouth scramble sparked by Morten Gamst Pedersen’s long free-kick was followed by what looked like a foul by Emmerson Boyce on David Hoilett, but Mark Clattenburg saw no reason to point to the spot.
Yakubu almost got onto the end of a Martin Olsson low cross with ten minutes to spare, but Ali Al Habsi did well to dive in for the ball first.
Anti-Kean and Venky’s chants had grown in volume as Rovers edged closer to the drop, and when Beausejour’s corner was converted by Alcaraz on 86 minutes they reached all-new decibel levels.
Hidden amidst the fury were the cheers of travelling Wigan fans, joyous at their latest miraculous escape after appearing certain to go down as recently as March.
Manager Roberto Martinez remained calm, raising a solitary arm in celebration of the goal, while scores of home supporters breached security to race onto the pitch in Kean’s direction as full-time confirmed their exit from the division they won back in 1995.