Some matches are always crucial. Some games do not need an injection of extra drama to enthrall. Manchester United versus Liverpool is one of them.

It is a rivalry of two cities distilled into 90 minutes of combativeness.

The two sides face each other again this Saturday. Imagine the pressure that comes from being at the heart of this game.

Imagine you are Brendan Rodgers. He arrives at Old Trafford after an uncertain start to the season with the shadow of former Dortmund manager Jurgen Klopp looming -- at least in the minds of supporters and the media.

This could be a defining game for the Liverpool manager.

Both matches against United last season proved to be turning points for Rodgers.

In December he took his side down the M62 with his job under threat. It had been made clear to the manager that Fenway Sports Group (FSG), the owners, were not enamoured with his team selections in the first half of the season.

Amendments were made and, although Liverpool lost 3-0, they were unlucky and played well.

It was a catalyst for a change in fortunes. They were about to embark on a 13-game unbeaten run.

Fast forward those 13 games and United were on the agenda again, this time at Anfield in March.

Rodgers was in a very different mood. Liverpool suddenly looked like a top-four side; they were in the semifinal of the FA Cup and, to hear the manager's side of the story, it was down to one man: Brendan Rodgers.

It was a compelling tale -- a journey from the brink of disaster to the edge of glory.

Eulogies to the manager's growing greatness filled the media.

Then, United came to town.

Louis van Gaal's team exploited the home side's tactical weaknesses, Steven Gerrard was sent off seconds into the second half after coming on as substitute, and although the 10 men produced a spirited last half hour, United won 2-1.

Liverpool's James Milner (L) is challenged by West Ham United's midfielder Manuel Lanzani. Photo: AFP

It was a huge step toward bringing Champions League football to Old Trafford, and sent Liverpool into a tailspin.

Which direction will Rodgers' team go after Saturday? This is a make-or-break season for the Northern Irishman's Liverpool career.

Nothing less than a top-four place and/or trophy will do.

Given that both sides started the season in an unconvincing manner, this match is an early chance to build confidence and land a significant blow to one of their main rivals' top-four hopes.

United's scatterbrained approach to the transfer window has brought derision down on Van Gaal and executive vice-chairman Ed Woodward, the man holding the purse strings.

They seemed to have spent more of the summer compiling lists of (sometimes unattainable) targets than actively pursuing players.

However, early in the window they strengthened the midfield with Morgan Schneiderlin and Bastian Schweinsteiger.

Van Gaal may see flooding the middle as the key to the game. Liverpool have failed to get the right balance there, and United could bully them in this crucial area.

Aside from Christian Benteke, Rodgers' side has a lightweight look. Emre Can has the power to put himself around, but his mobility throws up question marks.

Brute force, not talent, could well determine the direction of the points. United have an advantage here.

One of the biggest issues for Rodgers is leadership on the field. The 3-0 defeat by West Ham United at Anfield last month illustrated this.

At one down, Liverpool were still in the game. When the second goal went in, the team seemed to give a collective shrug.

There was no belief there was a way back. The lack of leadership is partly because FSG's transfer policy targets younger players.

It led to a vacuum of experience and knowledge in the dressing room. The problems are deeper, though. The senior players -- such as Martin Skrtel and Jordan Henderson -- lack the charisma and fortitude to lead.

James Milner was brought in to address this, but the former Manchester City man is no Graeme Souness.

Liverpool are too nice for their own good.

The consequences for Rodgers could be nasty.

He needs to solve the soft spot in the centre of the defence by developing a coherent midfield group that protects the back four and creates chances to get the best out of Benteke.

In the end, Rodgers needs the sort of upswing he got after the United game last December.

If the aftermath is anything like March's meeting of the two sides, Rodgers' time at Anfield may start to run out.