Real take on the Italians at the Bernabeu knowing a win or draw in Group C will see them through to the last 16 of the competition.

Should they lose to Lazio by more than one goal, and Werder Bremen beat Olympiacos in Greece, Real will be out.

And that is a scenario Guti does not want to think about.

"It will be like a final because if we don't win or if we earn a negative result we may be out of the Champions League," Guti told the club's official website www.realmadrid.com.

"A club as big as this one can't afford that to happen."

Beating Lazio will ensure Real Madrid top the group standings, while a draw will also be enough if Olympiacos do not beat Werder.

All group leaders have crucial home advantage in the second legs of their last 16 ties and Guti believes it is important for his side to finish top.

"Winning and going through as group leaders are the two important things to achieve in the game against Lazio," said Guti.

"We haven't had the chance of having home advantage in recent years. I hope we do this year. We are convinced of being able to win if we play as we have so far."

Despite suffering their first defeat of this season's competition at Werder Bremen last time out, Real can go into the game full of confidence having only lost one of their last 24 Champions League games at the Bernabeu.

With so much at stake, Guti is hoping the Real fans turn out in numbers to support the team on Tuesday night.

"The fans are excited with the team and they know much is at stake. The Champions League has a special flavour for us. The fans will be there for us in order to help us progress in the competition," he added.

Real Madrid coach Bernd Schuster should have no new injury worries to contend with and is only likely to be without injured defender Gabriel Heinze.

Lazio are bottom of the group, but can still qualify for the knockout stages if they beat Real by two goals or more and also if they win by a single goal and Werder fail to beat Olympiacos.

Only a win will be enough for the Biancocelesti and coach Delio Rossi is urging his players to put on a confident display.

"We have nothing to lose in the Bernabeu and we will go there and play without fear," he told the club's official website www.sslazio.it.

Having been hampered by injuries this season, Rossi's squad is beginning to return to health and defender Mobido Diakite is back in training although he has not travelled to Spain.