Inter were tied a 2-2 with Siena as Materazzi won a 78th minute penalty before arguing with teammate Julio Cruz on who should take the spot kick.

Eventually, the controversial defender stepped up only to be denied by Alex Manninger, who secured a point for his team at San Siro.

"I think last season the order of penalty-takers was the same, but at the time and today I felt like taking it. Unfortunately I made a mistake," said the Italy international.

"Perhaps with hindsight I should have left it to Cruz. I apologized to him afterwards."

Parma Decider

Inter boss Roberto Mancini admitted that Materazzi was not supposed to take the penalty ahead of Cruz, but gears up for next week's finale at Parma.

"The penalty takers were Cruz, Balotelli and then Materazzi. You can miss penalties, unfortunately, so Julio could’ve made a mistake too. You never know," said Mancini.

"Sometimes you feel like taking the penalty and you are not the taker. You feel it is right.

"We really could’ve done without that incident, but this is football and these things happen. Tonight the disappointment will pass and we will start preparing for Parma."

Should Roma win at struggling Catania next week, Inter have no option but to beat Parma, who are also fighting against relegation.

The Penalty Incident