The Nerazzurri were trailing 3-2 until the 88th minute before a Wesley Sneijder free kick and a Walter Samuel stoppage-time winner sent the home fans into jubilation.
Inter were without striker Samuel Eto’o, who is away at the African Cup of Nations, and it was the Milan side’s first match since the sale of Patrick Vieira to Manchester City was announced.
Speaking to the media after the game, the 46-year-old Inter boss said he would like to have more options available to him on the substitute’s bench.
“If we have a few injuries, it’s a problem. I had kids on the bench. I had to throw them into the fire,” said the Portuguese manager after the match.
“I would prefer to have a bench which gives me solutions.”
He went on to praise Siena’s spirited performance that had seen them score three goals in a thrilling encounter.
“Technically we were lost, tactically we had great difficulty,” Mourinho added. “Siena were better than us. They were calmer, had mobility, speed, they were good on the counter-attack.”
“They didn’t deserve to lose.”
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