Rafael Benitez's side were electrifying at Anfield as they crushed the Spanish giants 4-0 by suffocating the life out of them with high-tempo attacking football from the first whistle to the last. They could have scored 10.
Now think back to the 0-0 home draws with Stoke City and Fulham, the 2-2 with Hull City and the abysmal 2-0 defeat at Middlesbrough last month that all but raised the white flag of surrender as far as the Premier League title race is concerned.
Those listless performances will not be forgotten by Liverpool supporters desperate for the club to end the long wait for a domestic league title which stretches back to 1990.
Defeat at leaders Manchester United in the early kickoff on Saturday would snuff out any lingering hopes the Merseysiders have of snatching the crown back this season.
TWO LIVERPOOLS
Quite clearly there are two Liverpools.
There is the one that beat United 2-1 at Anfield and won 1-0 at Chelsea in the league, snatched victory at the Bernabeu and humiliated Real Madrid on Tuesday.
Then there is the one so easily bogged down in the trenches with the Premier League's mediocre sides, of which there are many this season.
Manchester United, seven points clear in the Premier League after an 11-match winning run, adapt easily to the differing demands of chiselling out league wins and turning on the style in Europe while rotating their squad.
Benitez has clearly still not mastered the first part of that conundrum.
Captain Steven Gerrard was phenomenal on Tuesday. Free of the shackles that sometimes leave him subdued, he drove at the heart of Real's defence with an energy and enthusiasm that proved infectious to his team mates.
Striker Fernando Torres, who bagged his first Champions League goal this season to send Liverpool towards victory, was a constant menace while behind them Javier Mascherano and Xabi Alonso provided a rock-solid midfield base.
The key, however, was the pace at which Liverpool began the game. "We stayed on top of them from the start," Benitez told reporters. "We had a lot of confidence and approached it in the right way. The atmosphere was very, very positive."
TACTICAL BENITEZ
Benitez is not an arm waver on the touchlines. He rarely displays his emotions, even when the goals are flying in as they were on Tuesday.
Instead, he relishes the tactics of football, setting up a side for a specific purpose as is often the case in big one-off European clashes.
The problem is that when the intoxicating atmosphere of Anfield on a Champions League night or playing one of England's big four in the Premier League is taken away Liverpool can quickly become becalmed, unsure of whether to play from instinct or stick rigidly to their pre-match instructions.
What has also become apparent is that when Benitez puts his strongest side on the pitch they are a match for anyb
