Benitez: Pennant must learn

The former Arsenal winger was dismissed after being shown two yellow cards in the Champions League group A opener in Portugal, which left the Reds to hang on for a point.

And Benitez said: "Hopefully Jermaine will learn from this experience. Maybe it will produce something positive for the future, the tackle in that position was just not needed."

He added: "It is difficult to understand why he did it, we had talked to him about staying on his feet and not making rash challenges.

"We were even talking on the bench about taking him off, but we just did not get the time to do it."

The Anfield chief admitted his side were not at the races in the first half, in which a Dirk Kuyt header cancelled out Lucho Gonzalez's early penalty, but was pleased with the response of his players after the break.

He sad: "We were really very bad in that first half, there are no excuses.

"We gave the ball away too easily and made too many mistakes. But the second half was much better. We needed to show real character and that is what we achieved.

"We were more organised, there was an excellent workrate and there were positives to be drawn from the second-half performance.

"We were playing against a good side and we have no complaints about the result."