Premier League: Top dogs Liverpool F.C. scent blood at Manchester United

Liverpool hold the whip hand over Manchester United for the first time in decades and could land a devastating blow on their rivals' top-four challenge at Old Trafford on Sunday. (Update: Liverpool F.C. thrash Manchester United)

Having endured year upon year of United supremacy, Liverpool have turned the tables this season and approach this weekend's match 11 points above their floundering foes in the Premier League table. (Also read: Liverpool F.C. more than just Suarez, says Rodgers)

While Liverpool still have eyes on the title, United's bid for Champions League qualification is in dire straits as they trail fourth-place Manchester City by nine points, having played two games more.

David Moyes's side have already lost at home four times in the league this season and they can expect no sympathy from a Liverpool team whose fans have endured season after season of torment at United's hands.

Not since September 2004 have Liverpool gone into a league game at Old Trafford above United in the table and it was 23 years ago -- in February 1991 -- that that was last the case for a fixture played after Christmas.

Only once, in 2002, have Liverpool finished above United in the post-1992 Premier League era, but current manager Brendan Rodgers has warned against paying too much attention to the relative fortunes of the two teams.

While Rodgers has been eager to play down Liverpool's title chances, he says that silverware, rather than success against United, will be the only reliable barometer of his team's progress.

"The benchmark for us is the best," he said. "First of all, we are always challenging the team at the top; not Manchester United, who are further down.

"Liverpool has its own great history both domestically and in European football, so for us the benchmark has always been the best and we will always look to do that.

"I never said when I came in here we wanted to be fourth. Top four is where we want to be, but Liverpool will always be judged on being the best, both here and in Europe, not against Manchester United."

- Van Persie commits future -

Devoid of distractions in the cup competitions, Liverpool have found fine form in recent weeks, winning seven and drawing two of their last nine league games.

Luis Suarez and Daniel Sturridge, the division's two leading scorers, have now amassed 42 goals between them, which is only four fewer than United's entire squad.

United enjoyed breezy wins over Crystal Palace and West Bromwich Albion in their last two league outings, but disaster has never been far away for Moyes this season and on Wednesday his side must attempt to overturn a 2-0 deficit against Olympiakos in the last 16 of the Champions League.

While the United manager concedes that Liverpool's league position "possibly" makes them favourites, he is hoping that the defending champions will be inspired by the magnitude of the occasion.

"It has been a great rivalry between the two clubs," he said in his pre-game press conference.

"Liverpool are having a very good season and we have to do everything we possibly can to beat them."

Moyes was buoyed on Friday by the news that last season's top scorer, Robin van Persie, had rubbished speculation about his future at the club by declaring that he is happy at Old Trafford.

Moyes can also now call upon winger Nani, who has recovered from a long-term hamstring problem, while centre-back Jonny Evans (calf) and striker Javier Hernandez (knee) could also be in contention to play.

Liverpool, who last tasted victory at United in March 2009, have been given a boost by the returns to fitness of midfielder Lucas Leiva (knee) and centre-back Mamadou Sakho (hamstring).

United won 1-0 when the teams last met, in the League Cup third round in September, and Moyes may take heart from the knowledge that Liverpool have lost -- by a one-goal margin -- on their last six visits to Old Trafford.