Zlatan Ibrahimovic
PSG have signed Zlatan Ibrahimovic Reuters

There was plenty of action at the Camp Nou on Tuesday night, as Spanish champions Barcelona welcomed their Italian counterparts, AC Milan, for a second leg, Champions League quarter-final tie. At stake was a place in the semi-finals and a match-up with either Premier League outfit Chelsea or Portuguese club Benfica.

The evening also marked the return (not for the first time, though) of former Barcelona striker Zlatan Ibrahimovic. The big Swede played for the Catalans during the 2009/10 season, in which he scored 21 goals from 44 appearances.

The match proved to be an exciting affair, with the hosts running out comfortable 3-1 winners on the night, thanks to two first-half penalties by Lionel Messi and an Andres Iniesta goal in the second period.

However, as has become the tradition with Barcelona's more high-profile European nights, the final whistle was followed by free-for-all accusations of referee bias towards the Spanish champions.

"I'm just disgusted," the Swedish international said in a Telegraph report, "They are the best team in the world but at 1-1 and, playing with intelligence, you can do something. (But) I understand better why Mourinho gets upset every time he plays here - in my opinion it was not fair."

Ibrahimovic was referring to an incident in the 40th minute, when Dutch referee Bjorn Kuipers booked Italian defender Alessandro Nesta for tugging at the shirt of Barcelona's Sergio Busquets inside the area. The incident began well before the ensuing corner was taken and really should have been dealt with by the referee before allowing the corner to be taken.

The penalty that was awarded was Barcelona's second of the game and, more importantly, restored their aggregate lead. Messi, who converted the second penalty, had earlier scored from another penalty before Milan's Antonio Nocerino leveled matters to put the visitors in the lead on away goals.

"The ball wasn't in play and he called it. It was weird, odd, it ruined the game," Ibrahimovic added, "I still don't understand what he whistled. If he calls those he should call the others. Without him the game would have been 50-50."

The forward was not the only Milan representative to feel hard done. The Italians coach, Massimiliano Allegri was also less than impressed.

"I don't know if the referees were decisive or not. In the first half we made a mistake with the first penalty and then the referee lent his help [to Barcelona] with the second one," Allegri is quoted as telling reporters after the game, in a Goal.com report.

"Unfortunately, we are out. I would have preferred it to be different, and not with two penalties, which seem as if they were awarded very easily. Playing against Barcelona is never easy," the manager added.

Barcelona coach Pep Guardiola was expectedly defensive of his team's performance and the result.

"You can talk all you want about referees but that makes it five straight semi-finals, the fruits of our talent and a lot of work," Guardiola explained.

Meanwhile, the man at the center of the storm, Bjorn Kuipers, has been quoted, in another Goal.com report, as saying he was pleased with his efforts and that of his team of officials.

"We [the match officials] put in a good team performance. The match went as we expected it to go," Kuipers is quoted as saying, adding he had no regrets about his decisions.

"The fact that we have a good feeling about the match says it all. My phone has been ringing non-stop, and it's nothing but compliments," he added.