ROMELU Lukaku’s 11th and 12th goals of the season fired classy Albion to a second successive win.
The on-Chelsea man broke the deadlock with a 35th-minute penalty and his third goal in just two games 15 minutes from time proved decisive.
Stephane Sessegnon gave Sunderland hope by pulling one back on 78 – but the back-to-form Baggies weren’t to be denied a deserved victory which propelled them to the so-called '40-point safety barrier'.
The Black Cats will be glad to see the back of both Lukaku and Albion. The striker also scored in Albion’s 4-2 win on Wearside in November and this was the Baggies’ sixth win in seven unbeaten Barclays Premier League games against Sunderland.
Ninth entertained 13th at a packed-to-the rafters Hawthorns as the Baggies returned to action some 12 days after their thrilling win at Anfield.
Clarke rang one change from that 2-0 success, with Graham Dorrans making way for top scorer Lukaku in a 4-4-2 formation. Peter Odemwingie also returned to the bench after a three-game absence.
Sunderland made two changes as injured duo Danny Rose and Lee Cattermole were replaced by Sebastian Larsson and Danny Graham.
After a low-key opening to the game, it was Albion who recorded the first effort at goal, but skipper Chris Brunt was well off target from 25 yards.
Sadly, that was the only goalmouth incident to report for some time in a match which was sorely lacking in quality during the opening stages, although not effort.
On 23, the Baggies threatened again when Liam Ridgewell whipped in a dangerous cross from the left. Lukaku rose highest at the near post but sent his header wide.
Then, out of the blue, came a real let off for the Baggies as they were guilty of two defensive errors in quick succession.
Claudio Yacob was dispossessed on the edge of his own area by Graham and former Wolves striker Fletcher struck the far post with a deftly-placed shot from 18 yards. Steven Reid pounced on the loose ball but his clearance ricocheted off Adam Johnson and found its way to Fletcher, who swiveled and fired over from 15 yards.
The game had suddenly opened up and it was Albion’s turn to go close on 25 when James Morrison strode onto Lukaku’s neat pass and saw his low cross fizz across the face of goal.
But Clarke’s men should have been ahead on 18. Lukaku slipped in Ridgewell down the left and the full-back picked out the unmarked Youssouf Mulumbu in the six-yard box who somehow headed wide.
There was further Baggies agony on the half-hour mark when the hosts argued that referee Roger East had blown his whistle for a Seb Larsson foul on Morrison too quickly. As Morrison went to ground, he poked the ball through to Lukaku who netted easily – but the ‘goal’ could not stand as East had already halted play. Reid’s resulting free-kick came to naught.
However, Albion did not have to wait too much longer to get their noses in front.
On 35, and after sustained Baggies pressure, East pointed to the spot when Ridgewell’s cross struck Craig Gardner’s arm in the box. Lukaku made no mistake from 12 yards, calmly stroking his penalty down the middle as Simon Mignolet dived to his left.
The goal was no less than Albion’s endeavour had deserved and they went close again when Shane Long flashed a header wide from Brunt’s free-kick.
Lukaku was having a terrific game and almost scored a wonder goal when he bustled his way past three Sunderland players before losing the ball in a congested penalty area.
More slick Baggies play resulted in Morrison whipping in a fine right-wing cross but Long failed to keep his header under the bar.
That proved the final action of a half that Albion had gone on to dominate.
Albion started the second 45 on the front foot but Morrison failed to trouble Mignolet with an ambitious 25-yard volley.
But Sunderland threatened themselves on 51 when Mulumbu was in the right place at the right time to hack off the line after Sessegnon had prodded Larsson’s corner goalwards.
The Black Cats were now enjoying their best spell of the game and Graham came within a whisker of making contact inside the six-yard box with Alfred N’Diaye’s wicked left-wing cross.
Albion regrouped and Jonas Olsson went close to adding a second on 58 when his flick header from Brunt’s free-kick flew just over.
Five minutes later, Mignolet was forced to make a fine near-post save to deny Lukaku after Brunt had dispossessed Larsson to set up the chance.
Lukaku was on the rampage again moments later when he dragged an 18-yard effort wide of the far post. This time, it was Morrison who had turned provider.
Clarke rang his first change on 66 when he replaced Long with Dorrans.
Albion were prodding and probing for another goal and Mulumbu tried his luck from 20 yards on 68, only to shoot straight at Mignolet.
They went even closer a minute later when it took a fine near-post tackle by Bramble to deny Morrison a certain goal from Dorrans’ low centre.
The Baggies pressure continued and after Sunderland failed to clear an Albion corner, Lukaku saw his acute drive pushed wide by Mignolet.
But the Belgium international wasn’t to be denied on 75. After skipping past John O’Shea, Bramble nipped in to dispossess the striker, only to under-hit his back-pass. To his immense credit, Lukaku chased down the loose ball and although Mignolet just beat him to it, the Sunderland keeper’s clearance cannoned off Lukaku and flew into the empty net.
The game wasn’t won yet, though. Sessegnon’s influence grew and, just a minute later, Ben Foster had to pull off a fine reflex save to deny the right-winger after a jinking run into the box.
However, Sunderland were back in it three minutes later. Sub James McClean’s low cross was diverted away from goal by Olsson but the ball fell to danger-man Sessegnon, who calmly curled home from 15 yards.
The win was suddenly in doubt but Brunt, who was enjoying a terrific game, almost made the points safe four minutes from time when he pounced on a Bramble error to unleash a wonderful volley from the edge the box. Mignolet arguably pulled off the save of the game to keep out the skipper’s effort.
Odemwingie made his return to action three minutes from time and almost scored within seconds, running at the Sunderland defence down the right before firing inches wide from an acute angle, with Mignolet beaten.
Sunderland piled forward in stoppage time and Foster was again called into action when he parried an awkward 20-yard shot from sub David Vaughan before gathering at the second attempt.
There was one final scare for the hosts – and a big one – in the 93rd minute. Jack Colback swung over a cross from the left which N’Diaye headed back into the danger-zone. The ball fell to McClean who miscued an awkward half-volley over from eight yards.
However, a Sunderland leveller – especially so late in the game – would have been rough on the hosts, who held on to secure their first home win since December.
ALBION (4-4-2): Foster; Reid, McAuley, Olsson, Ridgewell; Morrison (Fortune 84), Yacob, Mulumbu, Brunt; Lukaku (Odemwingie 87), Long (Dorrans 66). Subs not used: Myhill (gk), Jones, Tamas, Rosenberg.
SUNDERLAND (4-3-1-2): Mignolet; Gardner, O'Shea, Bramble, Colback; Sessegnon, N’Diaye, Larsson (Vaughan 75), Johnson (McClean 75); Fletcher, Graham. Subs not used: Westwood (gk), Bardsley, Kilgallon, Mangane, Cuellar.
GOALS: ALBION – Lukaku (pen 35 & 75). Sessegnon (78).
BOOKINGS: ALBION – Lukuku (removing shirt 75), Morrison (foul 78). SUNDERLAND – Bramble (foul 40).
REFEREE: R East (Wiltshire).
ALBION STARMAN: Romelu Lukaku.