Two of the Premier League's top four will go head to head this weekend when Chelsea welcome Manchester United and former manager Jose Mourinho to Stamford Bridge on Sunday.

The champions currently find themselves four points adrift of their opponents and a full nine off the relentless pace set by Manchester City, and another defeat this weekend could leave their title defence hanging by a thread.

United are also keen not to let City out of their sight, having overcome Tottenham Hotspur last weekend to establish themselves as the closest challengers, although they have only won once at Stamford Bridge since 2002.

Here, Sports Mole selects a strongest combined XI from the two squads in a 3-4-3 formation, using only the players available for Sunday's contest.

GK: David de Gea

Both teams possess world-class goalkeepers, but David de Gea is arguably the very best in the game right now and he showcased it again with another fine save against Benfica in midweek.

Thibaut Courtois has not been at his best so far this season, with Chelsea conceding 10 goals in as many games, whereas De Gea has continued to shine.

United boast the Premier League's best defensive record this term having let in just four goals in their opening 10 games, with De Gea keeping eight clean sheets in that time.

CB: Cesar Azpilicueta

A versatile and underrated gem of the Chelsea team, Cesar Azpilicueta is arguably the Premier League's most consistent performer and best out-and-out defender.

While his main strengths do lie at the back, the Spaniard has also showcased his attacking ability when playing in the right wing-back role this season and has two goals and four assists to his name across all competitions already this season.

With neither club captain seemingly guaranteed a place for either Chelsea or United at the moment, Azpilicueta also gets the armband in this team, comfortably holding off competition from Chris Smalling for a spot in the side.

CB: Eric Bailly

Last season this would have most likely been an all-Chelsea back three, but Antonio Conte has been chopping and changing this term and that has disrupted the form of their defensive unit.

In contrast, United look to have finally settled on their best defensive partnership and, whether playing in a back four or a back three, Eric Bailly has established himself as arguably Mourinho's first-choice centre-back.

Bailly has continued to build on a solid first season at Old Trafford to help United post the best defensive record in the Premier League so far, earning him a spot in this team ahead of David Luiz.

CB: Phil Jones

Phil Jones may have been significantly down the pecking order in this team last season, but this term he has arguably been United's most impressive defender.

The 25-year-old has started every Premier League game for the Red Devils so far this campaign and averages more clearances per game than any other player in either squad.

Jones faces stiff opposition in this team from the likes of Gary Cahill and Antonio Rudiger, but his performances this season earn him a deserved place.

RWB: Antonio Valencia

Having made his name as a winger before switching into a deeper full-back role, Antonio Valencia is perfectly suited to carry out the duties of an attacking wing-back down the right flank.

Victor Moses impressed in the role for Chelsea last season, but with the Nigerian injured Conte has switched between Azpilicueta and Davide Zappacosta in that position in recent weeks.

Even a fully-fit Moses probably would not keep Valencia out of the team, though, with the Ecuador international proving himself to be as adept at the back as he is going forward.

CM: N'Golo Kante

Injury has kept N'Golo Kante out of action since the last international break, but the PFA Player and FWA Footballer of the Year could be in line to return this weekend and even the suggestion that he might be fit is enough for him to win his place in this side.

Boasting more tackles per game than any other player from either squad, in addition to an interception count which only Luiz can beat, Kante had picked up where he left off last season before sustaining his injury.

Tiemoue Bakayoko has been impressive in his absence and is likely to keep his place in the Chelsea side ahead of Cesc Fabregas should Kante return this weekend, but there is no doubt who the main man in midfield is.

CM: Nemanja Matic

This weekend could provide an unwanted reminder for Chelsea fans as to what they lost with Nemanja Matic, and the decision to allow him to join one of their direct rivals remains a baffling one.

Matic has thrived since his switch to Old Trafford, providing a solid base for those in front of him to express themselves as United have gone on to score four goals in a game on four separate occasions already this season.

The Serbian has played every minute of United's Premier League campaign so far, and he may have a point to prove on his return to Stamford Bridge this weekend.

LWB: Marcos Alonso

Ashley Young has slotted into the left wing-back role well to help United with what was a problem area, but Marcos Alonso still takes his place in this team fairly comfortably.

The Spaniard has started all 10 of Chelsea's Premier League games this season and has quickly set about chasing his six-goal tally from last term, already finding the back of the net twice during the current campaign.

Alonso, like most of the Chelsea defence, could still improve at the back this season, but going forward he is one of the best wing-back exponents in the Premier League.

RW: Eden Hazard

Eden Hazard is yet to really hit full throttle in the Premier League this season having struggled with injury during the opening weeks of the campaign, but there is no doubt about his ability when he is at his best.

Despite the delayed nature of his start, the Belgian has scored three goals and set up two more in 12 appearances across all competitions, only eight of which have seen him named in the starting lineup.

Hazard's ring-wing position in this team would only be a rough starting role for the 26-year-old, who operates best when given a little more freedom to roam and wreak havoc in the opposition defence.

CF: Romelu Lukaku

As with Matic, Romelu Lukaku will return to a former club this weekend having never really made the grade at Chelsea. Sold by Mourinho only to then be signed by the same manager for United during the summer, the Belgian has gone off the boil a little in recent weeks following a blistering start to his career at the club.

Indeed, since scoring 11 goals in his opening 10 United games across all competitions, Lukaku is now without a goal in his last six outings, while he has never scored a Premier League goal against Chelsea either.

Lukaku still only trails Harry Kane in the Premier League's top-scoring ranks, though, with his tally of seven leaving him one goal above Chelsea's Alvaro Morata.

LW: Marcus Rashford

Probably the most difficult position to fill in this team, with the likes of Pedro and Henrikh Mkhitaryan amongst those vying for a spot in the front three, but Marcus Rashford gets the nod.

The England youngster has featured in all 10 of United's Premier League games so far this season, seven of which have come from the start, and in that time he has helped himself to three goals and three assists.

Add another two goals in both the Champions League and the EFL Cup to his name and Rashford has found the back of the net seven times across all competitions already this season, leaving him behind only Lukaku in United's goalscoring stakes.