MARC-ANTOINE Fortune's fifth goal of the season set up Albion's first win in five games against ten-man Blackburn - and the club's second league double of the term.
The former Celtic ace gave Roy Hodgson's men some much-needed breathing space by converting skipper Chris Brunt's centre in the 69th minute.
Albion had started the game in impressive fashion and broke the deadlock in the seventh minute when Martin Olsson hacked Gareth McAuley's downward header from Brunt's corner into his own net.
Liam Ridgewell's 85th-minute header - his first goal for the Baggies - sealed what looks on paper a comfortable afternoon.
But that only tells half the story and the Baggies once again had on-loan keeper Ben Foster to thank for today's precious points - particularly for his incredible 55th-minute double save to deny Yakubu and Bradley Orr.
Relegation-threatened Rovers' afternoon nosedived further when, two minutes from time, sub Anthony Modeste was red-carded for kicking out at Billy Jones.
Albion's fifth home victory of the season followed up their 2-1 success at Ewood Park in December, having also beaten Wolves at home and away.
Both teams entered the game on the back of two successive defeats as 14th entertained third-bottom - separated by eight points.
Hogdson rang three changes as Graham Dorrans, making his first start in eight games, Youssouf Mulumbu and Fortune came in for benched trio Somen Tchoyi, Paul Scharner and Shane Long
For Rovers, Steve Kean recalled David Dunn for Marcus Olsson.
Albion started like a house on fire and instantly put the visitors on the back foot.
In the third minute, Jonas Olsson towered above Grant Hanley and looped a header just wide from Brunt's corner before, moments later, Peter Odemwingie had a 25-yard strike deflected wide by Jason Lowe.
Blackburn launched their first attack in the sixth minute when Martin Olsson shot wildly wide from Junior Hoilett's pull-back.
But Albion were deservedly ahead a minute later. The hosts had already looked a real threat at set-pieces and after Brunt swung in another peach of a corner, McAuley saw his downward header sliced into his own net by Martin Olsson inside the Rovers six-yard box.
Blackburn had offered very little during the opening stages and Steven Nzonzi's 25-yard shot was diverted well away from Foster's goal by Jones' block.
The game then became something of a stop-start affair and it wasn't until the 23rd minute that either team threatened, when Rovers right-back Bradley Orr was off target with a far-post header from Martin Olsson's centre.
However, Albion still looked the team most likely to threaten the scoresheet, although Odemwingie was guilty of a wayward effort from 25 yards after neat Baggies build-up play.
Rovers did cause a moment of concern in the Albion penalty area on 32, though, when Scott Dann out-jumped McAuley to head Morten Gamst Pedersen's free-kick into the danger area, which Jonas Olsson hacked frantically over the Albion bar before a Rovers player could pounce.
The Baggies defended the corner and launched a terrific counter-attack which culminated in former Blackburn ace Keith Andrews sliding his cross just behind Odemwingie at the back stick.
Rovers had grown in confidence as the half progressed but Dann could only head Orr's inviting cross straight at his former Blues team-mate Foster in the 34th minute.
Back came Albion and after a neat spell of possession, the unmarked Mulumbu was inches away from connecting with Jones' right-wing centre inside the six-yard box.
Fortune was enjoying a terrific half and after a mazy run from the French Guyana ace, Mulumbu shot weakly at Paul Robinson from 18 yards.
But Albion had a let-off themselves on 43 when Hoilett jinked his way past Andrews and Mulumbu before curling wide from just outside the box.
Then, in the final minute of normal time, McAuley did well to block another Hoilett shot and David Dunn planted the rebound straight at Foster from just inside the box.
Blackburn started the second half as positively as they had finished the first and, with just 54 seconds on the clock, Pedersen muscled his way in front of Jones to head Orr's right-wing centre straight at Foster.
On 52, another Albion scare. Mulumbu miscued the ball into the unmarked Yakubu's path and the former Middlesbrough ace would have been clean through had Foster not been alert to the danger and raced out of his area to clear in the nick of time.
Foster came to Albion's rescue again three minutes later with a stunning double save. Firstly, he kept out Yakubu's 15-yard effort from Hoilett's lay-off before somehow getting in the way of Orr's follow-up.
As the Baggies struggled to keep possession, Blackburn attacked again and Yakubu sent a fine 20-yard effort inches over following more neat link-up play by Hoilett.
Rovers could count themselves unlucky not to be level as the clock ticked past the 65th-minute mark and Foster was again called into action, although he easily gathered Hoilett's tame 25-yarder.
The Baggies didn't really threaten again until the 67th minute when they won a corner and that came to naught, with Brunt eventually firing harmlessly into the side-netting from an impossible angle.
But the hosts had some real breathing space on 69 when Fortune fired them two-up.
Brunt dispossessed Yakubu on the right before seeing his left-footed centre brilliantly controlled by Fortune at the far post, who lashed the ball past Robinson from close range - his second league goal of the season.
Albion looked a far more composed outfit now and, after Blackburn had only half-cleared a Brunt corner, Ridgewell fired straight at Robinson from 15 yards.
Blackburn kept plugging away and a familiar pattern emerged on 77 - Hoilett shot straight at Foster from 25 yards.
But it was game over on 85 when Ridgewell got in front of Hanley to head Dorrans' free-kick past the helpless Robinson.
Blackburn's misery was complete on 88 when sub Modeste, who had only been on the field for ten minutes, was red-carded for kicking out at Jones.
ALBION (4-4-2): Foster; Jones, McAuley, Olsson, Ridgewell; Brunt (Cox 82), Andrews, Mulumbu, Dorrans (Scharner 88); Odemwingie, Fortune (Long 90+1). Subs not used: L Daniels (gk), Dawson, Tchoyi, Shorey.
BLACKBURN (4-4-1-1): Robinson; Orr, Hanley, Dann, Martin Olsson; Lowe (Formica 78), Dunn, Nzonzi, Pedersen (Modeste 78); Hoilett; Yakubu. Subs not used: Kean (gk), Givet, Petrovic, Marcus Olsson, Goodwille.
GOALS: ALBION - Martin Olsson (own goal, 7), Fortune (69), Ridgewell (85).
BOOKINGS: BLACKBURN - Dann (foul 51).
SENDING-OFF: BLACKBURN - Modeste (violent conduct 88).
REFEREE: L Probert (Gloucestershire).
ALBION STARMAN: Marc-Antoine Fortune.