KENNY DALGLISH has called for his Liverpool players to mix fiery hearts with cool heads when Manchester United visit Anfield this weekend.

The Reds boss believes discipline will be a key factor in Sunday’s lunchtime clash, in which Liverpool will be out to avenge defeats in both league and cup already this season.

The Reds currently lie sixth in the Premier League table, a full 21 points behind Alex Ferguson’s table-toppers

The most recent encounter between the sides, an FA Cup third round tie at Old Trafford in January, saw skipper Steven Gerrard dismissed in a narrow 1-0 defeat, and Dalglish, who turns 60 today, is keen to see his side retain their cool in what promises to be a red-hot atmosphere.

“Of course we know that this game means an awful lot to the fans, and everybody connected with the club,” said Dalglish.

“A lot of people look forward to games with Manchester United, but for us every game is important, and the most important one is always the next one.

“Discipline is important in any game, not just a game against Manchester United. It’s not hard for players to retain their discipline in games like this, it is just about controlling the aggression and the passion and using it sensibly.

“There are fine lines between strong tackling and committing a foul, as we have all seen. Players know that if they do something silly then they will be shown a yellow card or a red card, that’s the same in just about any game.

“We had that problem against Manchester United last time with Steven, and in this fixture Nemanja Vidic has had a few problems in the past – though he won’t be playing on Sunday as we know.”

That Cup defeat, settled by an early - and controversially awarded – penalty from Ryan Giggs, was the first time Dalglish had taken charge of the Reds since his dramatic return to the managerial hotseat. The Scot had spent the week prior to the fixture relaxing on a luxury cruise around the middle East, before answering the call to succeed Roy Hodgson.

He is better prepared this time.

Said Dalglish: “Obviously I never had any time with players ahead of the Cup game, I was in transit.

“The team were well prepared anyway, but of course everything went out of the window in the very first minute with the penalty decision, and then Steven being sent off. It’s hard to plan for things like that.

“Hopefully that won’t be happening again on Sunday.”

United will make the journey down the East Lancs Road with defensive concerns, with Rio Ferdinand (injury) and Nemanja Vidic (suspension) both absent, but Dalglish has been handed a considerable fitness boost, with the news that Raul Meireles, Daniel Agger, Fabio Aurelio and Sotirios Kyrgiakos have all returned to full training following recent knocks.

The Reds boss also revealed that record signing Andy Carroll has recovered fully from the thigh strain which has thus far stunted his Anfield career, and that the 22-year-old is in contention for a place in the squad for Sunday.

“The news is pretty positive on our injured players,” said Dalglish.

“We’re hopeful most of them will be fit, but we don’t really know because it’s a wee bit away from the game yet.

“Obviously Martin Kelly won’t play with a hamstring strain and Jonjo Shelvey won’t be available either. Everybody else’s fitness is more positive than that. Who we have and what we go with we won’t know yet – and that includes Andy Carroll.

“Andy’s training was always progressing but it hasn’t progressed into a game yet.

“We’ve said all along that we’ve been delighted with his progress and there hasn’t been anything he’s done that hasn’t been encouraging.

“Whether he’s involved on Sunday or not – I’m sure Fergie would love to know but we don’t know.

“And anyway, he might not even be a substitute – he might be going to see Boyzone!”

One man Dalglish is expecting to feature on Sunday is Wayne Rooney.

The United striker has been at the centre of attention of late, having controversially escaped FA punishment following an off-the-ball elbow on Wigan’s James McCarthy last weekend, but has also scored five goals in his last five league outings, and Dalglish is eager to ensure he doesn’t add to his tally come Sunday.

“Wayne Rooney doesn’t have to justify his footballing ability to anyone,” said Dalglish.

“He’s a top player, but he is not the only threat Manchester United have.

“He can be hard to keep quiet when he is on form because he is a match-winner.

“But we have plans, that’s what we’re here for, and hopefully we will be able to keep him quiet on Sunday.”