Paul Pogba red card hands Manchester City the Premier League title

It was a moment of over-exuberance that will become one of the defining moments of the Premier League season. Paul Pogba's stretched lunge towards Hector Bellerin on Saturday earned him a straight red card, but while Manchester United claimed the win over Arsenal, it is Pogba's suspension that will have the biggest impact on their title challenge.

The French midfielder will now miss the crunch derby match against league leaders and title favourites Manchester City next weekend. It is a massive blow for Jose Mourinho and his side as much as it will be a boost for Pep Guardiola and Manchester City. It is a must-win match for United as they chase their rivals, but their pivotal playmaker will play no part.

Pogba returned to United in the summer of 2016 for a world record transfer fee, and the significant investment emphasised how important it was for Mourinho to bring him back to Old Trafford. His value to the side was never more apparent than during his recent injury, and while his side maintained their title challenge, their overall game was lacking, without him.

The departure of Pogba was a key moment in the managerial career of Sir Alex Ferguson. It represented a changing time and culture as his power and control over young players appeared to be waning. Pogba challenged Ferguson due to his lack of game time, and moved to Juventus in the summer of 2012 to launch his career.

Jose Mourinho will have to make significant tactical changes without Paul Pogba

Having to buy him back a few years later for a world-record fee represented some pretty bad business, but Mourinho was only fixing the stubborn mistakes of a previous reign. Pogba has been worth every penny this season now that he has evolved and transformed himself into the role that Mourinho believes will bring the very best out of him.

The difference in Manchester United with and without Pogba in the side is significant, and it stretches beyond what he provides in his influential position in the middle of the field. A charismatic and confident character, the Frenchman brings the best out of those around him through his passionate approach, and that is without touching on his technical ability.

A towering, powerful presence, Pogba is as influential in defence as he is in attack, and he has the ability to create something out of nothing. He is a man that must be closely marked by the opposition, and he creates space for those around him as a distraction that cannot be ignored. There is a different energy about Manchester United when Pogba is in the side.

Mourinho got one over on old nemesis Arsene Wenger at the weekend, but the attempts on goal that Arsenal created will raise concerns for Mourinho as he plans to neutralise the attacking force of Manchester City. Before his red card, Pogba would have had a huge role to play in Mourinho's tactical approach for this crucial match, but now he must return to the drawing board.

Paul Pogba's red card could be the deciding factor in the Premier League title race

And that is because Pogba is that important to Mourinho's Manchester United side. Without him, the entire tactical plan for taking on Manchester City must be revised. Pogba is irreplaceable to United when the plan is to defend, as no alternative can offer anything like him. In his absence, Mourinho will need to pack his midfield far more than he would need to with Pogba in his team.

For Guardiola and Manchester City, Pogba's suspension offers an opportunity to be even braver in attack, and it is an opportunity that Guardiola will embrace. His team is built to attack in numbers across the field, and without Pogba's destructive ability, his players will have the time and space to practice their attacking footballing perfection.

Pogba's suspension will hurt Manchester United and Mourinho. It is a game they must win, but the most effective method of restricting Manchester City will be to park the proverbial bus. A draw will suit City more than United as Mourinho has points to make up on the formidable leaders, but his key midfield man will be missing through a moment of avoidable misjudgement.

The odds will favour Manchester City despite the match being played at Old Trafford, and Pogba's suspension is a key reason why. Mourinho cannot make any positive tactical change on the back of the absence of his key midfielder, and he will cut a frustrated figure as he considers what are now limited options on how to get the best from his side.

The match against Manchester City is one Jose Mourinho cannot afford to lose

The victory over Arsenal was one of the games of the season, but while next week's fixture will be a defining match in the title race, it already promises to be anything but a classic. Mourinho and Guardiola have a long-standing rivalry, and the Portuguese's attempts to frustrate the free-flowing football of his latest managerial nemesis have brought mixed results.

Paul Pogba returned to Manchester United with unfinished business to win trophies with the club that developed him through his formative years. However, his actions in the build-up to a defining game in the title race appear set to cost him a Premier League winner's medal this season, but his absence will also serve to emphasise his value to the side.