Elsewhere, West Brom continue to make hay while the sun shines
Liverpool's title hopes were dealt a pretty substantial blow on Monday afternoon, twice relinquishing their lead away to strugglers Sunderland and settling for just a point at the Stadium of Light.
There was more bad news on top of that. Daniel Sturridge limped off in the second half. Sadio Mane, who has scored nine league goals, is now off the African Cup of Nations. Suddenly things feel a lot less peachy on Merseyside.
Well, on one side of Merseyside. Everton made the most of their recent good form with a 3-0 win over Southampton who now have lost their last three games on the bounce.
Further good news for Ronald Koeman is the fact that Belgian Romelu Lukaku got himself back on the scoresheet for his second goal in three games.
West Brom came from behind to keep Hull City in the relegation zone. They scored three second-half goals to see them run out 3-1 winners at the Hawthorns. They've won four of their last five home games.
Manchester City will bemoan Fernandinho's discipline after today's 2-1 win over Burnley. The Brazilian picked up his third red card in his last six games. Sergio Aguero scored the winner after being dropped from the starting line-up this afternoon.
In the day's late game, Mike Dean courted controversy (not for the first time) for his first-half sending off of Sofiane Feghouli. United went on to win the game 2-0 thanks to goals from Juan Mata and Zlatan Ibrahimovic and extend their winning run to six games.
Here are some of the top talking points from a busy day of Premier League action.
On two occasions this afternoon, Liverpool led Sunderland. Their opener came from Daniel Sturridge who Liverpool fans will be happy to see get back amongst the goals. They were less pleased to see him hobble off 10 minutes from time.
Sadio Mane popped up for their second and again his performance has shown that he has been one of Liverpool's best players this season.
But, crucially, they couldn't hang on. Twice they conceded penalties. Twice Jermain Defoe stepped up. Twice he scored.
Games like those are games which define seasons. Teams chasing titles are judged as much upon their ability to see out potentially tricky games like that as to big victories against fellow challengers. It can all fall apart in smaller games, which today for Liverpool it did.
Not completely, of course. A point is better than nothing. But in a race where teams are starting to pick up momentum with consecutive wins, contenders need to be closing those games out.
Contrasting fortunes: Today's result was a huge point for Sunderland, but two dropped crucially for Liverpool. Image: Owen Humphreys PA Wire/PA Images
To the anger and frustration of Fantasy Football players everywhere this afternoon, Sergio Aguero found himself on the bench.
City needed a win today to keep get them back in the hunt for a place in the top four and were without their most potent striker from the off.
Things got worse when Fernandinho - for the third time in his last six games - was sent off. It's simply unacceptable for a player as important as he is to City to be building up so much suspension time.
In any case, Gael Clichy scored the opener for City just before the hour mark. But it was four minutes later when we really saw who City's most important player really was.
Aguero picked up a loose ball in the Burnley area. With two players on the and from an incredibly tight angle over to the right hand side of the goal, the Argentine somehow managed to squeeze it in.
It was his 153rd goal for club, bringing him joint third alongside Colin Bell as the club's all-time leading goalscorers.
Guardiola will be frustrated at the performance in places and Fernandinho's poor disciplinary record. But if you have someone like Aguero to bring off the bench, you're always in with a shout.
Sergio Aguero didn't start this afternoon but was on hand to score the winner against Burnley.
Robert Snodgrass scored the opening goal in what could have been a long afternoon for West Brom. In front of a home crowd, they fought back to secure a 3-1 victory.
The win constitutes their fourth win in their last five Premier League games at the Hawthorns. Of their last 10 matches they have won six: Hull (H), Southampton (A), Swansea (H), Watford (H), Burnley (H) and Leicester (A).
Their three defeats in that run came against Arsenal, Chelsea and Manchester United. The latter two are in the middle of highly credible winning streaks.
In truth, Tony Pulis can't have expected much from three defeats and has undoubtedly got the most out of the results from the teams around them.
They side comfortably within the top 10 (8th), just one point behind Everton. Wins like these, against teams who would be considered to be the same calibre of West Brom, are incredibly positive. Results like that keep them out of relegation scraps and up challenging for European spots or at the very least, a top half finish.
Gareth MacAuley scores to put West Brom ahead against Hull City. Image: Mike Egerton PA Wire/PA Images
Referee Mike Dean once again found himself in the spotlight this afternoon in the game between West Ham and Manchester United at the Olympic Stadium.
His first half red card seemed rash and after just 15 minutes, the home side were down to 10. They never really recovered and were forced to absorb a lot of pressure for the remainder of the half.
Not for the first time has he found himself at the centre of controversy and Garth Crooks' analysis of the referee seems even more relevant more than a year after Dean was again involved in the middle of a different red card scandal - Gabriel Paulista's against Chelsea.
A timely reminder of Garth Crooks on Mike Dean. pic.twitter.com/sxKdM5cSxO— Andy Ha (@_AndyHa) January 2, 2017