Furth schocks Schalke with late winner
Michel Bastos marked his Schalke debut with a goal, but Felix Klaus levelled before Djurdjic scored a dramatic late winner for Mike Buskens' men.
The win will be particularly sweet for former Schalke player and coach Buskens and striker Gerald Asamoah, who remains a terrace hero in Gelsenkirchen.
Robbie Kruse put Dusseldorf in control of the game with a brace before Christian Gentner brought Stuttgart back into the running.
Oliver Fink then sealed victory for Fortuna, who edge up to within a point of their opponents, who were unable to respond to coach Bruno Labbadia's decision to sign a contract extension during the week.
Lakic, who arrived in Frankfurt on loan from Wolfsburg just prior to the transfer deadline, grabbed a brace in the first half at the HSV Arena as the Eagles extended their advantage over fifth-placed Mainz to six points and denied Hamburg a place in the top six for the first time all season.
Frankfurt completed the double over Hamburg, inflicting their first home defeat after four wins in a row, and boosting their hopes of playing Champions League football next season.
Kevin Volland, the only player in the Hoffenheim squad to have found the back of the net since the turn of the year, was on target twice to earn them a much-needed win which lifts them back out of the bottom two and above Augsburg.
Max Kruse had put Freiburg in front before Volland's brace turned the game around and left them empty handed in a Baden-Wurttemberg derby.
Augsburg kept up their fine form in 2013 with a creditable draw at Wolfsburg, giving them further hope of retaining their Bundesliga status.
Jan Moravek earned the visitors a point with a 25th minute equaliser - two minutes after Naldo had put the Wolves ahead.
Augsburg have picked up five points from their first three matches of the new year, although Hoffenheim's victory over Freiburg saw the Bavarians slip back down to 17th in the table.