Two losses in succession since the summer break had left Goteborg trying to break free of the bottom three, but three points at home has seen them swap places with Degerfors for the time being.
They were given a huge helping hand in the 33rd minute, when Mads Hansen was rightly shown a straight red card for kicking out at Noah Tolf following a coming together.
In took time for Goteborg to make the man advantage count, but when Tobias Heintz curled a corner into the area in the 54th minute, Rockson Yeboah leapt highest to power it into the back of the net with his head.
But when a hopeful clearance was misjedged by Tolf on halfway, Oliver Berg was allowed a free run at goal, beautifully chipping the ball in off the post to put the Bromma Boys back on level terms.
However, Blavitt weren't going to let another opportunity pass them by, and 11 minutes from time, another corner made the difference, albeit via a goal-mouth scramble that finally ended with Sebastian Clemmensen firing into the roof of the net after multiple blocked attempts.
IFK are three points clear of the bottom three, while BP are three points further clear in 11th, having lost two in a row and not won in four.
Not for the first time this season, Mjallby have failed to beat a newly-promoted side at home. This time they were held by Vasteras who climb a place to seventh and are now three positions above the reigning champions, who sit 10th and without a win in six league games.
Elliot Stroud, back from the World Cup, played the full 90 minutes for Mjallby despite a move away from Hallevik reportedly almost finalised. He was unable to inspire his side in a match that had zero big chances for either side, as Aki Samuelsen struck two of the game's five efforts on goal.
MAIF will hope for better when they make their UEFA Champions League bow against Lincoln Red Imps on 21st July, while Vasteras have now taken seven points from their last three matches.
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