ROME (AFP) Inter Milan ruined Walter Zengas homecoming by beating Palermo 5-3 in an eight-goal thriller at the San Siro on Thursday. Zenga had threatened to upset his former employers as his battling team fought back from a 4-0 half-time deficit to within a goal with a quarter of the game remaining before Diego Milito settled things late on. Former Italy goalkeeper Zenga, who spent 12 years as an Inter player, was given a standing ovation when he arrived but his team was then ripped apart in a painful first 45 minutes, seemingly making a mockery of his pre-match claims that his side would challenge for the title. And while the first goal was due to some horrible home-team refereeing, thereafter Palermo simply could not handle Inters bristling attacking play as Samuel Etoo and Mario Balotelli each bagged a brace. Inter boss Jose Mourinho admitted he was annoyed at his teams second half performance. Obviously I was a bit angry and a bit worried because the game should have been over, he said. That can happen if a team loses concentration, it was a great comeback by Palermo. Away to a big team at 4-0 youd have thought theyd be trying to keep the score down but instead they went going for it. Zenga was left rueing an uncharacteristic defensive performance. At the end of the first half we conceded three goals that shouldnt have, that were unusual for us, he said. But we did great to come back into the game, we showed great personality and desire. Inter are now four points clear at the top of Serie A ahead of Juventus who thumped third-placed Sampdoria 5-1 on Wednesday. The lead came on 7min when the referee laughably awarded the hosts a penalty after Balotelli tried to run through an inexistent gap between two defenders and fell over. The teenager then tried to take the penalty off Etoo only to be dragged away by captain Javier Zanetti and he threw a mini tantrum as Etoo lashed home the spot-kick. If that goal had been unfair on Palermo, the Sicilians could have no complaints about what happened in the rest of the half. After Palermo goalkeeper Salvatore Sirigu, who played very well, had tipped a deviation off defender Dorin Goian from Etoos cross onto the post, Esteban Cambiassos driven centre came too quick for Balotelli who headed wide with his eyes closed. Sirigu made saves from Maicon (twice) and Etoo before Julio Cesar pushed away a fierce Fabrizio Miccoli free-kick up the other end. Just past the hour mark Cambiasso lashed a close range shot over the bar but on 34min it was two as Balotelli rose above Australian Mark Bresciano to head home Maicons corner. Palermo collapsed just before the break as Sirigu and Simon Kjaer got in each others way leaving Cambiasso free to head goalwards before Balotelli got the last touch on the line. And two minutes before the break the 19-year-old teed up Etoo to beat Sirigu at his near post. At 4-0 at the break the game seemed over but Palermo came out after the restart in determined mood and showed just why Zenga has so much faith in them. Miccoli started the comeback on 49min as he latched onto a long Simplicio through ball, held off Ivan Cordoba and chipped Julio Cesar. That seemed to be little more than a consolation but just past the hour mark teenage Uruguayan substitute Abel Hernandez tapped home a Mattia Cassani cross at the back post. And midway through the half a stunning reverse ball from Cassani with the outside of his boot and without looking much like Ronaldinho almost copyrighted during his Barcelona days released Miccoli between Cordoba and Davide Santon to again dink the ball over Julio Cesar. But seven minutes from time a tired-looking Palermo defence wilted and Maicon teed up substitute Milito to tap home the eighth goal of the night from close range.