Rafael Benitez upset over Ryan Babel red card in Lisbon
Babel committed the offence right in front of the referee
Liverpool boss Rafael Benitez was left frustrated with the decision to send Ryan Babel off in the Europa League quarter-final defeat at Benfica.
The Reds go to Anfield for the second leg trailing 2-1 having played for over an hour with 10 men after Babel was shown red for a hand in Luisao's face.
"It was not a serious offence. I'm disappointed with the decision but we can't change things now," Benitez said.
"We have to move forward, prepare for the game and score the goal we need."
The visitors got off to a fine start with a Daniel Agger strike inside nine minutes, but were reduced to 10 men on the half-hour in an incident beginning with a reckless tackle on Fernando Torres.
Luisao hacked the Spanish striker from behind and when the yellow card was brandished by Swedish referee Jonas Eriksson, Babel stepped in and pushed his hand into the defender's face in front of the official.
It was a decision that ultimately turned the game in favour of the Portuguese league leaders with Oscar Cardozo going on to score two second-half penalties to secure the victory.
The Spanish manager added: "It was strange. I was surprised because a foul from behind is more serious.
"I would like to analyse the foul before. And after, when one player is shouting in front of the referee after he already has a yellow card.
"It is a big difference when you kick a player from behind to a player touching another in the mouth."
Babel later admitted he felt "very guilty that we lost because it could have been a different situation".
"But we cannot turn back," he added. "Hopefully we can swap the result next time. It is good to know my team-mates are backing me up, and they didn't let me down. We are still confident we can go into the next round."
Needing to score in the return leg in Liverpool on Thursday, 8 April, Benitez remained upbeat about his side's chances.
"I prefer to be calm and be positive," he insisted. "We made some mistakes but we have to be positive and think about the next game.
"The team was working very hard and with the fans behind us we can progress in the competition.
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