Having inadvertently sparked Liverpool's mid-season revival with a 3-0 victory at Old Trafford in December, Manchester United visit Anfield in the Premier League on Sunday determined to suppress it.
Liverpool had taken only 21 points from a possible 45 prior to that trip to Manchester -- losing six of their first 12 games -- and the defeat left them 10 points below United in 10th place, seven points off the top four.
In the aftermath of a turbulent close season that saw Luis Suarez leave for Barcelona, it left manager Brendan Rodgers facing difficult questions about his capacity to take the team forward, but that bleak December day was to prove the catalyst for a spectacular turnaround.
Rodgers surprised observers at Old Trafford by sending Liverpool out with a three-man defence, but despite the final score, his side impressed, and it is with the same fluid 3-4-1-2 system that last season's runners-up have rejuvenated their campaign.
They have gone 13 league games unbeaten since losing at United -- winning eight of their last nine fixtures -- and victory on Sunday would lift them above their fierce rivals and into the Champions League places.
United's own form dipped following the win over Liverpool and although they have only been beaten twice in their 13 games since, manager Louis van Gaal has come in for criticism over the lack of creativity in his side's attacking play.
However, United blew off the cobwebs last weekend with a stylish 3-0 dismantling of Tottenham Hotspur and Rodgers believes the criticism of Van Gaal has been unjustified.
"He has shown over his career that he is a top-class manager," said the Northern Irishman.
"He will have seen, coming into this country for the first time, the challenges of this football. It is why it is the most competitive league in the world.
"The Premier League is different from the leagues he will have worked in before, but I don't think you can argue with his credentials.
"There is no question about the philosophies he has put in place at Ajax or Barcelona or his achievements, and when he leaves Manchester United he will still be one of the great managers."
- Gerrard swansong -
Sunday's encounter has been lent extra significance by the fact that all of the two clubs' rivals for a top-four place -- Manchester City, Arsenal, Tottenham and Southampton -- tasted victory on Saturday.
The trip to Anfield continues a decisive run of games for United that will also feature encounters with Aston Villa, champions City and leaders Chelsea, and Van Gaal knows how significant victory would be.
"I want to win against them again. It's very important," the Dutchman said.
"I think every player knows the importance of this game. We are in a very crucial stage and cannot lose."
Van Gaal has Angel di Maria available again after a one-game suspension, but the Argentina winger is not certain to return to the starting XI after Juan Mata impressed in the win against Spurs.
Left-back Luke Shaw is out with a hamstring injury, while fellow defender Marcos Rojo is a doubt with a groin complaint and Jonny Evans is serving a ban for spitting at Newcastle United's Papiss Cisse.
Liverpool midfielder Lucas Leiva faces a late fitness test, having spent six weeks on the sidelines with a groin problem, while Mario Balotelli is back after illness forced him to miss Monday's 1-0 win at Swansea City.
Captain Steven Gerrard is also in contention to start, having returned as a substitute at the Liberty Stadium following a month-long absence with a hamstring injury.
It will be Gerrard's last opportunity to face United -- against whom he has scored nine times -- before he leaves for the Los Angeles Galaxy, but with stand-in skipper Jordan Henderson and Joe Allen in excellent form, he may have to make do with a seat in the dug-out.
Source: AFP