DESPITE A second-half rally from Sunderland, West Browmich Albion climbed, temporarily, into third place in the Premier League, leaving Sunderland three clear of the drop zone.
Goals from Zoltan Gera and Shane Long, who profited from a Simon Mingolet clanger, put Steve Clarke`s side 2-0 up before substitute Craig Gardner pulled one back. Romelu Lukaku`s late penalty looked to have killed the tie off before Stephane Sessegnon bagged a late consolation. Marc-Antoine Fortune finally put the game to bed in injury-time.
Martin O`Neill unsurprisingly stuck with the same XI which beat Fulham at Craven Cottage last Sunday, whilst Steve Clarke made two changes to his side.
In came Gareth McAuley for Gabriel Tamas, whilst Chris Brunt returned in place of Youssuf Mulumbu in midfield.
Goalkeeper Ben Foster was still not fit enough to return to the side, so Bo Myhill continued between the sticks with Luke Daniels his deputy.
Adam Johnson had the game`s first chance when he cut into the penalty area from the left before firing a low shot into the palms of Myhill at the near-post.
Sessegnon was next to come close for the Black Cats when he hooked the ball over and Albion defender before poking a volley towards goal off the outside of his boot, Myhill equal to the effort.
Sessegnon and Larsson combined in the 24th minute, the latter meeting the former`s free-kick with a flicked header with Myhill could only claw away from a Baggies` defender cleared for a corner.
In the 29th minute West Brom took the lead when Gera collected a short pass before curling a superb left-footed effort right into the corner of the net and beyond Mignolet.
Sunderland immediately got back into the Baggies` half, Lee Cattermole sending in a left-foot cross which John O`Shea controlled before curling narrowly wide of the far-post.
That was to be Cattermole`s last action; the skipper withdrawn after taking a knock to the knee in delivering the cross.
Sessegnon had another opportunity shortly before half-time, somehow keeping the ball in down the left before bursting into the penalty area and shooting low into the palms of Myhill from the edge of the area.
Disaster immediately followed for the Black Cats when the normally reliable Mignolet dropped a clanger.
An over hit pass from Brunt was gathered routinely by the Belgian who somehow contrived to lose control of the ball, allowing Long to nip and tap into an empty net to double Albion`s lead.
Substitute Gardner troubled Mignolet`s opposing number from the re-start, cracking a venomous free-kick straight at the palms of Myhill who was unconvincing in keeping the ball out.
Mignolet went some way to repairing the damage his howler caused when he rushed out to meet his nemesis Long in the second period, blocking the Irish forward`s effort on the edge of his 18 yard box.
Johnson tested Myhill again seven minutes after the break, collecting Danny Rose`s cross-field pass before advancing and cracking a testing left-footed effort at the Welsh international.
Brunt nearly provided a third when he sent a teasing low cross into the middle, two Albion players unable to connect despite stretching to meet the centre.
Gardner pulled the Black Cats back into the contest with 17 minutes remaining, crashing a right-footed free-kick over Myhill and into the top-corner from way out on the left-hand touchline.
With just under 11 minutes to play, Sunderland were dealt a cruel blow when referee Mike Dean adjudged Johnson to have brought down Liam Ridgewell inside the penalty area. The former Aston Villa and Birmingham City defender looked to have dived following replays.
Up stepped substitute Lukaku to drill home a confident left-footed penalty, restoring his side`s two-goal lead.
Lukaku could have added a fourth when he beat Mignolet to a loose ball, but the Chelsea loanee was only able to pull across the empty face of the goal.
With four minutes to play, Johnson forced a strong palm from Myhill at the near-post when he cracked in a left-footed effort.
From the resulting corner Steven Fletcher`s headed was clawed into the path of Sessegnon who buried from close-range to reduce the deficit.
The Black Cats continued to pile on the pressure, Carlos Cuellar`s looping header caught by Myhill in the second minute of four added on before Lukaku`s footwork saw him engineer enough space to crash a shot off the inside of Mignolet`s near-post.
Almost inevitably, West Brom scored a fourth with the seconds slipping away as the Lads pressed harder and harder.
Lukaku drove forward, picking out strike partner Fortune to finish coolly from six yards.
Sunderland: Mignolet; Bardsley, Cuellar, O’Shea (McClean), Rose; Larsson, Cattermole (c) (Gardner), Colback (Saha), Johnson; Sessegnon; Fletcher.
Subs not used: Campbell, Kilgallon, Vaughan & Westwood (GK).
WBA: Myhill; Jones, McAuley, Olsson, Ridgewell; Yacob, Morrison; Odemwingie (Fortune), Gera, Brunt, Long (Lukaku).
Subs not used: Popov, Rosenberg, Dorrans, Tamas, & Daniels (GK).
Referee: Mr M Dean.