With Premier League leaders Manchester City facing off against Arsenal earlier in the day, the match at Stamford Bridge could start with United eight points behind their neighbours, and Chelsea a further four back.
So this could just be the game neither side can afford to lose – but will either be brave enough to win?
While the most entertaining battle may already have been played out, as managers Antonio Conte and Jose Mourinho have traded subtle barbs all week, here’s a look at the key battles which will be played out on the pitch.
Luiz has had a tough time of late, putting in some erratic performances as Chelsea’s rearguard has descended into a shambles. The Brazilian’s imperious form from last season has disappeared, while the indisciplined game that Conte had seemingly stamped out has begun to return.
Perhaps the battle against Lukaku is just what he needs. Luiz isn’t the first name you think of when you consider defenders who relish a physical battle, but having one single player to focus his energies on might help him.
He’ll always back himself to win duels on the ground (whether he actually does so as often as he’d like is up for debate) and it’s possible he could rise to the aerial challenge.
For Lukaku, it’s a chance to end a six-game goal drought, show Chelsea what they missed out on by not signing him, and silence the critics who say he doesn’t perform in big games. No pressure, then.
It’s likely he’ll try positioning himself Cesar Azpilicueta as often as possible to take advantage of his height and physicality, but he’ll have his fair share of battles with Luiz as well, and he could just exploit the vulnerabilities that have creeped back into the Brazilian’s game.
When Eden Hazard sees the United team on Sunday, he might shudder when he notices Ander Herrera. The Spaniard shackled Hazard brilliantly when these two sides faced off in April.
However, United had a three-man midfield that day, which gave Herrera the license to follow Hazard.
United don’t have enough fit senior midfielders to play a three-man midfield at the moment, so Herrera will have to stick to his role in the centre of the park, leaving Hazard the only slightly easier challenge of squaring off against Antonio Valencia.
The right-back is having a typically understated, impressive season, but Sunday will be a stiff challenge. Hazard has just begun rounding into form, and his pace and trickery will give any defender nightmares.
United fans like to think of Valencia as the best right-back in the league; on Sunday, he’ll have to earn that billing.
Like Lukaku, Morata hasn’t scored in his last six games, although he does have the mitigating circumstances of having spent time out due to injury.
Also like his striking colleague, he bagged an assist in a 1-0 win in his last Premier League outing. And in another similarity between the duo, the Spaniard is now coming in for a fair bit of criticism for his form.
So he’ll be as determined as his opposite number to make a mark on this game. Morata has scored in a Champions League semi-final and final before, so he doesn’t have a reputation of falling short in big games to knock back. But he will nonetheless have a formidable obstacle to overcome in Phil Jones.
The Manchester United man is having his most impressive campaign in years, so much so that Sport360 declared he’s the best centre-back in the league when he’s on form.
He’s equally adept at dealing with a physical striker like Morata’s predecessor, Diego Costa, and a player whose game is based more on movement and finding space, like Morata himself. This should be the game’s most closely-fought battle.
Chelsea finished 10th in 2015-16 as Leicester won a title no-one had predicted before the Blues succeeded the Foxes as champions in Conte’s first season in charge last term.
Title-winning boss Claudio Ranieri was sacked as the Foxes flirted with relegation last season, while Jose Mourinho was fired seven months after leading Chelsea to the trophy in 2014-15.
Conte does not fear the same fate.
“I have to stay with my fingers crossed,” said Conte with a smile ahead of Sunday’s Premier League clash with Manchester United.
“Honestly, I think I earned my time here with the win of last season.
“I don’t like to ask for time. I like to tell the truth. The situation is very clear: my task is to work and to put all myself for this club. Then if it’s enough? OK. If it’s not enough? OK. The same. I will continue to live.
“If we think I click my fingers and we are ready to fight. It’s not simple. Last season happened. A miracle.
“It was a miracle, because we had the same players that the season before finished 10th.”
Conte’s position has been the subject of conjecture as Roman Abramovich has regularly wielded the managerial axe during his 14 years as Chelsea owner.
The Blues entered this weekend’s fixtures nine points behind leaders Manchester City and after a chastening 3-0 Champions League loss at Roma on Tuesday. Mourinho would welcome doling out a significant blow on his former employers.
Conte admits he is not a patient man as he seeks to find consistency for Chelsea, who have performed brilliantly at times this season, but also abjectly.
And he says he has explained to Abramovich and the Chelsea hierarchy of the need to overhaul a squad shorn of the heroes of the last decade of success, which began with Mourinho’s first spell at the club.
Conte said: “We must be ready to do something special. But we must be realistic and to understand that we are building. We are creating a foundation.
“It’s important to have the patience and then to have the time to do this.
“I understand that it’s not for all to have patience – I have not a lot of patience, honestly. But patience is a big quality.”
Asked how Chelsea’s “miracle” compares with Leicester’s, Conte added: “Chelsea’s name sometimes covers the miracle, only because your name is Chelsea.”
Conte is hoping to welcome back N’Golo Kante – a title winner with Leicester and Chelsea – against United after a six-match absence with a hamstring injury.
Danny Drinkwater could start in the Premier League for the first time alongside his former Leicester team-mate, while Conte says Gary Cahill will start in defence despite his early tactical substitution in Rome.
Having failed to complete the signing of the Chilean in the summer, City have gone on to tear the league apart without him, scoring 35 goals in 10 league games so far this season. They’ve got a five-point lead at the top of the table and they’re nine points clear of Sanchez’s Arsenal side, whom they entertain on Sunday.
Gabriel Jesus and Leroy Sane have six league goals each, while Raheem Sterling – for whom Arsenal proposed a swap deal in order to facilitate Sanchez’s move – has seven. Pep Guardiola‘s decision to flat-out refuse to include Sterling is clearly paying dividends. The Englishman has chipped in with two assists, as well, while Jesus has one and Sane has five.
And then, of course, there’s Sergio Aguero, with his seven league goals and three assists.
Sanchez has one goal and two assists in seven appearances this season. Per 90 minutes, his goal (0.20 vs 0.40) and assist (0.40 vs 0.41) stats are down in comparison to last season, although he is actually creating more chances. It’s not even as if the drop-off can be attributed to the arrival of Alexandre Lacazette, because until a couple of weeks ago the duo hadn’t been on the pitch together.
More than just the numbers, Sanchez just doesn’t look like the player from last season. He hasn’t been the all-conquering force he was for Arsenal in the previous campaign, when it seemed like it was only his efforts that were keeping the team afloat.
So why would City want him?
On pure talent, of course, Sanchez is one of the best players in the league, if not in Europe. But the Jesus-Sterling-Sane frontline has been so devastatingly effective for City, with or without Aguero. Indeed, Guardiola is comfortable enough to rest or drop Aguero because of his youthful trio (Sterling is the oldest – and he’s only 22), and the Argentine is in the same strata of players as Sanchez.
So it’s fair to ask, would the Chilean really improve City?
There is a sense that Sanchez is at his best when he’s the main man. Certainly, that’s how he’s thrived at Arsenal, and at Udinese, where then-manager Francesco Guidolin made him the focal point of the team.
Conversely, he struggled (by his own high standards) to have the same impact when he was one of many at Barcelona, where he had one excellent season sandwiched by two middling ones – with caveats: injuries and the arrival of Neymar limiting his playing time.
But if he does move to City next summer, he’ll be in a similar situation to what he faced at Barcelona, and under the same manager.
Guardiola might be an admirer of Sanchez’s but the same issue will exist: the league leaders have many outstanding attacking players, and Sanchez won’t have a team that’s built around his strengths and where he’s the focal point.
So if he wants to make a point to his potential employers on Sunday, showing that he has to carry Arsenal might not be the best way to do it. That’s not to say he shouldn’t try to take over the game if that’s what Arsene Wenger‘s side needs on the day. But everyone knows he can score a cracking goal and generally thrive when the play is going through him.
What’s more important for him to display is a willingness to buy into a team ethos. Lead his teammates through his actions, by encouraging them rather than showing his frustrations, by abandoning his “woe is me” look that surfaces whenever Arsenal struggle in a game and by playing to the team’s strategy rather than trying to do everything on his own – until the moment it’s absolutely necessary.
He needs to play like he’s the best player on a very good team. Not like he’s miles better than his teammates, he knows it, and he’s sick of it. Because he won’t be if he moves to City.