The hitman condemned Andrea Stramaccioni's men to defeat in Javier Zanetti's 600th match, in what was another poor showing that leaves them adrift of third place
Inter entered the match on the back of a disastrous 3-0 loss at the hands of Tottenham on Thursday, and were desperate for points to keep up pace on the upper echelons of Serie A.
Coach Andrea Stramaccioni handed evergreen captain Javier Zanetti his 600th Serie A appearance in a Nerazzurri shirt, as Dejan Stankovic, Marco Benassi and goalkeeper Juan Pablo Carrizo found their way into the line-up amidst the ongoing injury crisis. Antonio Cassano was conspicuously absent from the starting XI as he returned to the squad following an alleged bust-up with his coach.
Gilardino and Alessandro Diamanti led the line for the visitors, and it was the latter who nearly sent Stefano Pioli's men into a first-minute lead. Picking himself up after being fouled by Fredy Guarin, the Italy international produced a sumptuous delivery onto the head of Frederik Sorenson, who headed narrowly over the crossbar.
Undaunted by the fiery San Siro atmosphere, it was the Rossoblu who dominated the opening exchanges as they continuously found avenues to advance down the right flank. Striker Manolo Gabbiadini delivered the next series of warning shots, coming close to opening the scoring in quick succession. The Juventus loanee first blasted a cut-back into the side-netting, before holding off the challenge of Juan Jesus to incredibly fire straight into the arms of debutant Carrizo.
Pressure on the hosts' proved unrelenting as Stramaccioni's men failed to come to grips with their opponents' endeavour, Gilardino and then Diamanti becoming the next to try their luck against a creaking Inter backline. Nevertheless, Bologna custodian Gianluca Curci had to be alert at the other end to keep out a looping Rodrigo Palacio header, the Argentine recording his side's first attempt on target on the 20-minute mark.
That rare respite failed to galvanise Inter into producing anything meaningful throughout a lacklustre first period however, as Benassi and Walter Gargano failed to dislodge Bologna's stranglehold on the midfield. Play grew heavily congested in the middle as Zanetti and co. struggled to stem the tide, and it was the Dall'Ara outfit who headed into the break still very much in the ascendancy.
Cassano was afforded a rapturous welcome after being introduced to inject some impetus, and Ezequiel Schelotto immediately earned the Milan giant's first corner of the evening. Exerting the first period of real pressure on the Bologna area, it was Stankovic who narrowly missed connecting with Juan's measured pull-back, as the ball bobbled agonisingly past the 34-year-old's outstretched foot. The injury-hampered veteran then had an excellent scoring opportunity charged down by the opposing defence, paying the price for a moment's hesitation.
The writing had been on the wall all match however, and it was Gilardino who emphatically fired Bologna into a deserved lead. The flag stayed down as a searching ball found the Italian, who made no mistake from his precise volley to fire the ball past a stranded Carrizo.
Curci then did well to leave his line to smother a through-ball for Palacio, before comfortably dealing with a Guarin pot-shot straight down his throat. Ex-Nerazzurri midfielder Rene Khrin then had his header parried beautifully by Inter's beleaguered custodian, as the home side clung on for dear life.
A crucial last-ditch intervention by Gyorgy Garics on substitute Esteban Cambiasso and Andrea Ranocchia's towering header apart, Bologna saw out a comfortable final 15 minutes to secure a credible victory and pile further pressure on Stramaccioni's position in the dugout.
The defeat, combined with Fiorentina's 2-0 victory over Lazio, sees Vincenzo Montella's men leapfrog them in the chase for qualification for the Champions League next season. Meanwhile, Bologna sit comfortably in the table on 35 points, having ensured survival as the final stages of the season beckon.