John Hartson
BBC Radio 5 live

"For Manchester United it will be a good test against Chelsea to see how far they have come. I did not think they would finish in the top four but they have really impressed me. They kept plugging away and got the results and have turned a corner. Fellaini has become a top player for them. It will be an interesting game, all the pressure will be on Chelsea. They can not rest on their laurels."

Chelsea make two changes from the side who beat QPR last time out in the Premier League as Kurt Zouma and Oscar start with Ramires & Willian on bench.

Luke Shaw, Radamel Falcao and Paddy McNair are brought in for Manchester United, who are without the injured quartet of Michael Carrick, Daley Blind, Phil Jones and Marcos Rojo. Striker Robin van Persie is included on the substitutes bench.

Chelsea XI: Courtois, Ivanovic, Cahill, Terry (c), Azpilicueta, Zouma, Matic, Oscar, Fabregas, Hazard, Drogba.

United XI: De Gea, Valencia, Smalling, McNair, Shaw, Mata, Rooney, Herrera, Young, Fellaini, Falcao

Former England midfielder Danny Murphy
Football Focus

"Manchester United will do well to get a result at Stamford Bridge today, with all the players they have out injured. Michael Carrick is the main man out, it's a huge blow for them. And for Arsenal too because I think that swings the title firmly into Chelsea's path."

Andrew Tuffnell: Could this be the day Radamel Falcao proves class is permanent? If he wants a contract next year, now's your time to get it...

Jamie, Lincoln: Three centre-backs on the field. This is why Chelsea don't deserve the league. Utterly boring.

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Kurt Zouma v Wayne Rooney in midfield then - a key battleground. Or will Zouma go man-to-man on unlikely United hero Marouane Fellaini?

BBC Sport chief football writer Phil McNulty at Stamford Bridge

"Radamel Falcao has never been able to seriously impress since making his loan move to Manchester United - but he gets a big opportunity here at Chelsea today in a Manchester United side struck by injuries. It is likely to mean Wayne Rooney dropping into midfield, so what a chance for the Colombian to make the impact he has craved since arriving from Monaco.

"Still no Diego Costa or Loic Remy for Chelsea so manager Jose Mourinho will hope Didier Drogba can roll back the years against opponents he has tormented before."

Kevin Kilbane
BBC Radio 5 live

"The way the Chelsea manager Jose Mourinho goes about these bigger games is that he would take a 0-0 draw. If he can nick a goal then he will sit on it. I can't see him playing open expansive football in this match."

If Chelsea are (slightly) stuttering toward the end of the season, Manchester United are just getting going,.

Only Arsenal have taken more points in the Premier League in 2015 and Louis van Gaal's side smashed rivals City last weekend.

Image source, Getty Images

A win at Stamford Bridge today would see United move to within five points of the leaders.

An unlikely late title challenge from Old Trafford?

Chelsea have been top of the Premier League since 18 August.

They have looked like champions from the moment Andre Schurrle scored a majestic team goal on the opening weekend of the season. Diego Costa settled into the top flight like a dream, Cesc Fabregas reminded everyone just how good he was, Eden Hazard was a one-man wrecking ball and Thibaut Courtois formed a human wall in nets.

They were in a league of their own.

They still are to be honest - seven points clear of the chasing pack - but has the mask just started to slip?

Three unconvincing wins in a row against Hull, Stoke and QPR have posed a few questions - and now Manchester United are in town.

Image source, Getty Images

Can United pick up another big win to shake up the tail-end of the season?

Chelsea

Chelsea: Courtois, Ivanovic, Cahill, Terry, Azpilicueta, Zouma, Matic, Oscar, Fabregas, Hazard, Drogba

Man Utd: De Gea, Valencia, Smalling, McNair, Shaw, Mata, Rooney, Herrera, Young, Fellaini, Falcao

BBC Sport chief football writer Phil McNulty at Stamford Bridge

"West London is bathed in glorious sunshine and thousands of fans are already milling around outside Stamford Bridge ahead of Premier League leaders' Chelsea's meeting with Manchester United.

"Jose Mourinho may be the master now as Chelsea hold a seven-point advantage over Arsenal at the top of the table with a game in hand but his one-time mentor at Barcelona Louis van Gaal may just think the door to the title has been pushed slightly ajar if United can win here and reduce the gap on Chelsea to five points."