Arsene Wenger was left fuming by a refereeing decision he claims cost Arsenal victory over Liverpool in their Champions League quarter-final.

The all-Premier League tie remains finely balanced after Emmanuel Adebayor put the Gunners ahead at the Emirates only for Dirk Kuyt to peg the visitors back to 1-1.

But Wenger believes Arsenal could have won the game if referee Pieter Vink had decided to award a penalty to the home side when Alexander Hleb appeared to be pulled back by Dirk Kuyt in the penalty area.

"It's difficult to understand how we did not win the game, we had a lot of possession and a lot of chances," Wenger told Sky Sports.

"We were a bit unlucky as well with a big decision of the referee on the penalty. It's difficult to take but we have to swallow it.

"Sometimes the referee is in a bad position but he was five yards away from Kuyt and it was 100%."

Arsenal dominated possession in the second half, but could not convert that superiority into victory - something Wenger struggled to understand.

"The game was played in one half in the second period and it was difficult because Liverpool defended well," he said.

"I think Kuyt played second right-back and on the other wing they defended deep and it was difficult to find space."

Liverpool manager Rafa Benitez said the television replays he had been shown were inconclusive.

"It was difficult to tell," he said. "You don't get penalties like that in England, it is not very clear."

Benitez added that the timing of Kuyt's first half equaliser was crucial.

"If you concede a goal against Arsenal it is really important to score as soon as you can," he said.

"The away goal was very important for us. We are in a good position with the home game to come at Anfield in front of our own supporters.

"However it will still be very difficult for us. Arsenal are a very good team and it is going to be very tough."

And Kuyt insisted the referee was right not to award a penalty.

"It's just a split second you have to decide," said Kuyt.

"I didn't pull his shirt. It was never a penalty - but it was close."

Speaking about the game, Kuyt added on Sky Sports 2: "We did everything we could - we wanted to score and we did.

"After the goal, we came back in the game and had a few other little chances. They have a great performance, and we did everything we could.

"We have shown in European nights at Anfield we were really good and we hope we can do the same next week and go through to the semi-finals."

TeamTalk / Eurosport