Samuel Eto'o snatched a late equaliser after Sampdoria had threatened to end Inter's unbeaten home record after 18 months.
Benitez complained that Antonio Cassano fouled Cristian Chivu during Sampdoria’s goal, but hailed Inter’s “character.”
“At the start we had control of the game, while Samp played on the counter-attack,” said Benitez of the 1-1 draw.
“Then we conceded this goal where Cassano fouled Chivu in the build-up. You could see that he looked at the linesman, because he knew it was a foul.
“This complicated our game. Today the referee did not do a good job.”
Inter seem to score considerably more goals in the Champions League than they do in Serie A.
“Italian sides are tactically very strong indeed, so it’s tougher to score against them. Besides, injuries to Diego Milito and Goran Pandev don’t help. When everyone will be fully fit, it will make things much easier.
“I am happy with the way the team reacted after going a goal down. The side showed character.”