BIRMINGHAM: Rafael Benitez is confident Liverpool will regain their Premier League focus in Sunday's clash at Birmingham after a stormy Europa League defeat to Benfica.

The Reds visited Portugal in the first leg of their Europa League quarter-final and, although they took the lead courtesy of a Daniel Agger goal, they had Ryan Babel sent off and eventually lost 2-1.

Despite the scoreline, it was a brave performance from Liverpool and Benitez was pleased with his side's showing.

Yet before the second leg at Anfield on Thursday, Liverpool, who are four points behind fourth placed Tottenham in the table, have to overcome a difficult visit to St Andrew's.

Alex McLeish's men have been one of the surprise packages of the season and although they were expected to be relegation contenders, they sit comfortably in the top half of the Premier League, having lost just twice at home all term.

Benitez is wary of the threat Birmingham pose to his hopes of guiding Liverpool to a spot in the top-four come the end of the season and as a result, he does not want his squad looking ahead to Benfica.

"It will be another tough game. The Premier League is always very difficult so we will have to bring the players back quickly and be ready," Benitez said.

Liverpool's task will be made harder by the expected absence of midfielder Alberto Aquilani, who is a doubt with an ankle problem.

Aquilani's injury, similar to the one which he had when he arrived on Merseyside after his pre-season transfer from Roma, ruled the Italy international out of the Benfica clash.

He is likely to miss out again alongside injured defenders Martin Skrtel and Fabio Aurelio.

Birmingham are unbeaten in their last 12 home games but they have managed just three victories in 12 encounters so far in 2010.

That statistic does not worry City boss McLeish too much and he wants his players to savour the experience of playing against Benitez's side now that their Premier League future is secure.

"I have tried to say to the players from day one to enjoy the Premier League because this is a spectacular moment in their lives," McLeish said.

"When you stop playing football you will say there is nothing in your life that compares to playing at the highest level.

"This game comes into the glamour side of the Premier League because they are one of the best teams.

"We knew we had to win our bread and butter games this season, which we have done and that is why we are staying in this division but we have also done well against the big guns, especially at St Andrew's.

"There is no doubt that we are in for a hard game but we have to show Liverpool we are a very difficult side to play against, especially at home."

McLeish has no new injury concerns but remains without veteran midfielder Lee Carsley and striker Garry O'Connor.