Barry Nicholson was Dunfermline's goal hero for the second time in two games with a first-half strike against Dundee.
The former Rangers player netted after just 12 minutes to allow the Pars to move up to fifth place in the Scottish Premier League table.
Nicholson salvaged a draw against Celtic in the Scottish Cup on Saturday with a last-minute goal, and tonight his goal gave the Pars all three points.
Dundee manager Ivano Bonetti was forced to field a depleted side, as injuries take their toll on the Dens Park side.
And Dunfermline tried to take advantage by having a go after just three minutes. Justin Skinner's long ball into the area was met by David Moss just outside the six-yard box. He tried to control the ball to have a shot but the danger was cleared by Chris Coyne.
After just 12 minutes the Pars were ahead.
A Stevie Crawford flick found Barry Nicholson, who unleashed a shot that deflected off Marcello Marrocco into the back of the net.
A couple of minutes later, the Dundee players appealed for a penalty, insisting the ball had come off the arm of Andrei Skerla from a Beto Carranza shot but referee Tom Brown waved play on.
After 25 minutes the referee had to leave the park after being hit by the ball. He looked to have sustained a painful arm injury and had to be replaced by fourth official Colin Hardie.
Dundee came close to levelling the score after half an hour. Steven Milne released Willie Falconer, whose strike produced a great one-handed save from goalkeeper Marco Ruitenbeek.
The big Dutchman came to the rescue again 10 minutes later. This time it was Carranza who sent the cross in to Falconer just a few yards out but the keeper managed to block the effort.
Milne had taken a knock earlier in the game and looked to have added to Bonetti's injury worries when he had to be replaced by Michael Yates just before half-time. Carranza was also swapped for Lee Wilkie.
Chris McGroarty had the first chance of the second half but pulled his shot wide after 46 minutes.
Three minutes later, substitute Wilkie had a great chance to draw level when he got on the end of a Javier Artero cross only to nod just over the crossbar.
Skerla became the first player to be booked in 52 minutes for a challenge on Claudio Caniggia.
Wilkie had another golden opportunity to grab the equaliser after 53 minutes but tried to take the ball too far and Ruitenbeek was able to scoop up.
At the other end a couple of minutes later, the Pars almost added to their lead. Moss went on a good run before exchanging a one-two with Scott Thomson but nodded tamely into goalkeeper Marco Roccati's hands.
With just 10 minutes remaining Dundee were determined to grab the goal that would ensure a share of the points.
They continued pushing forward and Artero came close with a long-range effort which was well held by the goalkeeper.
Six minutes later substitute Marco Russo had a go but pulled his shot well wide.