Sitting in 2nd place in the EPL, above their crosstown rivals Manchester City, United are off to a pretty good start.
However, they are currently 4 points behind league-leading Chelsea and a win in this Sunday fixture would be huge in their quest for a title.
Even with their success so far, there have been some areas of concern. The following 4 players will need to step up in order for the Reds to get a victory.
While United's offense got major upgrades in Shinji Kagawa and Robin Van Persie, their defense was not improved at all over the summer, and they are beginning to be seen as the Achilles heel of the team.
Despite their six wins in eight games, United have already conceded 11 goals. They have lost Phil Jones, Chris Smalling and Nemanja Vidic to injury, and Ferdinand's lack of speed is often exposed and exploited. Their struggles have included performances in which they allowed Fulham, Southampton, and Stoke City to each score two goals, not to mention allowing three in a win against Tottenham.
With United's defense in shambles, Ferdinand needs to act as a leader and step up his play. The same type of defensive performance from the back four will result in much more than two goals against a team like Chelsea.
Even if Rio Ferdinand and the rest of his teammates in the back 4 step up their play, they will still have a tough time covering Chelsea's attackers, and will need help from whoever Sir Alex opts to start in goal.
With the likes of Eden Hazard, Juan Mata, and Fernando Torres, Chelsea have put away 19 goals in their first 8 games, scaring teams with the pace of their wingers and strikers.
The blame can't be placed on United's goalkeepers for the 11 goals conceded so far, but they'll need to be at their best for the Reds to win this match.
Yes, you read that right, attacking midfielder.
With Shinji Kagawa out for a month, the England international will probably take the reigns in this playmaking role. Rooney will be able to display his passing abilities, a talent of his that is hard to notice when he's playing as a striker.
Ultimately, as an (attacking) midfielder, Rooney will be able to help out more on defense and possibly win the game for United if he set the forwards up in front of goal.
With Wayne Rooney filling in Shinji Kagawa's void at attacking midfielder, it looks like Hernandez will fill the empty void at forward based on his recent performance.
Although he's been rarely used in league play, that should change soon as he netted two goals in a 3-2 Champions League win vs Braga and has scored in each of his last two games for Mexico. While he'll most likely have Robin Van Persie beside him, Hernandez will be relied on to keep up his form and do what he does best vs. Chelsea: poach and score.
Truthfully, Chicharito's goal-scoring ability never really declined; he just hasn't been given much chance to show it.