Kevin Phillips made an instant impact from the bench to give Blackpool the points against in-form Millwall.
Among the substitutes for the second time in a week, Phillips had only been on the pitch for two minutes when he found the top corner on the hour.
The striker almost doubled his tally with five minutes left when he scuffed Neal Eardley's cross against the post.
Millwall had found the net 10 times in a run of three straight wins but rarely threatened until near the end.
But their late onslaught ran out of steam and Ian Holloway's side held out for back-to-back victories for the first time since the opening games of the season to move into the play-off places.
After some quiet opening exchanges, Blackpool midfielder Keith Southern brought the game to life in the eighth minute.
First, Lions' goalkeeper David Forde tipped his well-struck 25-yard drive around the post. From the resulting corner Southern found space for a free header that was cleared off the line by Jack Smith.
With 20 minutes gone, Smith proved less reliable when his untimely slip allowed Eardley to advance down the right and cut back to Southern who skied his effort.
Lomana LuaLua, fresh from a midweek brace on his full Blackpool debut, charged at the visiting defence in the 25th minute and skilfully shifted the ball onto his left foot to bring a great save out of Forde.
Millwall finally made an impression on the Seasiders when top scorer Darius Henderson peeled off to the far post and steered Liam Feeney's corner goalwards, only for man-of-the-match Alex Baptiste to intervene.
Baptiste caused some set-piece problems of his own at the other end but headed over when he connected with Ludovic Sylvestre's delivery.
The deadlock remained until Holloway withdrew Southern to introduce Phillips and, within minutes, he made the vital breakthrough with a sublime curling shot on the turn from the edge of the box.