Marcelo Zalayeta scored his first two goals of the season to give Bologna just a second win in seven Serie A games.

The Uruguayan struck either side of half-time before Marco Di Vaio rounded off victory in injury time.

Simon Kjaer had equalised after Zalayeta's first goal, but Palermo could not break down a resilient home defence after the interval as their winless run extended to three games.

The visitors were the first to threaten, though, and Bologna keeper Emiliano Viviano had to be quickly off his line to prevent Edison Cavani reaching a dangerous through-ball after the forward had sprung the offside trap.

Di Vaio was close to an opener for the hosts following a neat passing move which also involved Roberto Guana and Nicola Mingazzini, the latter's cross just too far in advance of the onrushing striker.

Viviano made a fine save at full stretch from Federico Cassani's left-footed drive and then recovered to repel the ball when it was turned back into the penalty area.

But he was beaten by Fabrizio Miccoli's low 20-yard drive in the 34th minute, the ball clipping the left post with the motionless keeper breathing a sigh of relief.

And Bologna made the most of that let-off as they took the lead eight minutes later.

Di Vaio battled for possession with the Palermo defence and, after bundling his way through and coming up against keeper Salvatore Sirigu, he unselfishly squared the ball for the unmarked Zalayeta to tap into the opposite corner of the net.

That lead, however, lasted just three minutes before Denmark defender Kjaer slid in to tap home a free-kick before Viviano could gather the ball.

That was a fair reflection of an evenly matched first period, but Bologna were back in front just four minutes after the interval.

Roberto Guana's through-ball sent Zalayeta clear and he held off Giulio Migliaccio to finish coolly beyond the advancing Sirigu.

Igor Budan immediately threatened an equaliser with an acrobatic effort from the right side of the penalty area, but Viviano leapt to turn the ball behind for a corner.

The Bologna defence was holding firm, although they had to survive a moment of eccentricity from Viviano after the keeper came off limits at the edge of his penalty area and was forced to dribble past both Abel Hernandez and Miccoli before getting the ball to safety.

That was as close as Palermo came to a second equaliser, though, and the impressive Di Vaio put the result beyond doubt in the third minute of stoppage time when he dispossessed Kjaer and broke away to beat Sirigu.

The win saw Bologna leapfrog both Lazio and Atalanta to move three points clear of the relegation zone in 15th place while Palermo slipped further adrift of the push for a European place to lie just four points ahead of their opponents.