Goals from Jerome Thomas and Shane Long secured a second home league win of the season for West Brom against struggling Bolton.
The two strikes separated a controversial penalty from Ivan Klasnic and gave the Baggies a deserved three points after a dominating second-half performance.
The Bolton striker had pulled his side level after Thomas was ruled to have brought down Fabrice Muamba in the penalty area.
The Trotters played well in the first half although they had trailed when Thomas had got on the end of Zoltan Gera's through ball before rounding the goalkeeper and scoring.
After the break, however, they were completely outplayed and deservedly went down to Long's header after 56 minutes.
Gary Cahill, celebrating his 150th Premier League appearance, went close early but his effort was cleared off the line by Youssouf Mulumbu.
Cahill then had to be alert at the other end to deny Long after he had been put through by Thomas. The centre-back made a sliding challenge to deny the Irishman.
However, Bolton failed to take the warning seriously and were behind moments later. Gera this time put the through-ball to Thomas who side-stepped Jasskelainen and slotted home in the 16th minute.
The visitors didn’t have to wait long and just like three weeks when Liverpool were in the West Midlands, it was from a controversial penalty.
With the ball hanging in the air from a Wanderers corner, Fabrice Muamba climbed over a standing Thomas to try and win the ball and was rewarded when referee Neil Swarbrick gave a penalty.
Klasnic was on target in his last match for the Trotters and he made no mistake, coolly sticking it in the corner to level the match up after 21 minutes.
Wanderers were starting to get on top and a mazy dribble by Mark Davies, which saw him beat three West Brom players, was only stopped by the legs of Foster as he shot across goal.
The home side came out for the second half in determined fashion and they had the Bolton back-line under pressure for the first 10 minutes.
Eventually it was Long who did the damage, rising home to head Shorey's first-time cross after good work from Thomas on the left.
Bolton nearly equalised straight away, but after Klasnic flicked the ball on in the home penalty area, Olsson managed to use his strength to force Kevin Davies to shoot wide.
However, the Baggies should have doubled their advantage after good work on the left saw Shorey tee up Thomas in the area but, unmarked, he could only pick out Jaaskelainen in front of him.
In the end West Brom comfortably held out to move further away from the relegation zone.