Zlatan Ibrahimovic celebrates with his Manchester United team-mates

Manchester United have moved within four points of the Champions League places after winning three consecutive Premier League games for the first time since August.

Jose Mourinho's side followed up their victories over Tottenham and Crystal Palace with a comfortable 2-0 win against West Brom at the Hawthorns on Saturday.

The winning streak has provided a much-needed boost after a stuttering start to the season, but what's behind their upturn in form? We look at five contributing factors...

Ibrahimovic on target again

One of United's biggest problems throughout September and October was their inability to convert presentable scoring chances, with Zlatan Ibrahimovic only finding the net once in 11 appearances after scoring five in his first five.

The Big Swede spurned eight clear-cut opportunities during that barren period - more than any other player in the Premier League - and his misses were particularly costly in United's defeats to Manchester City and Watford and their draws against Liverpool, Stoke, Burnley and West Ham.

Watch highlights from West Brom 0-2 Manchester United Watch highlights from West Brom 0-2 Manchester United

The loss of confidence and composure in front of goal was alarming, but Ibrahimovic has rediscovered his scoring touch as quickly as it deserted him. Since netting twice in United's 3-1 win over Swansea at the start of November, the 35-year-old has hit 10 in nine appearances.

From struggling to convert straight-forward chances, Ibrahimovic is now finding the net from all angles. His winner against Crystal Palace was a brilliantly instinctive, diagonal finish, and his second against West Brom was another reminder of his enduring ability to conjure goals out of nothing.

Ibrahimovic has also emerged as leader capable of bullying opposition defences, and with 11 Premier League goals he is now only two behind top scorer Diego Costa. His importance cannot be understated, and the veteran striker is showing no signs of fatigue.

Pogba's best position?

Mourinho has finally settled on a system which suits Paul Pogba perfectly. The world-record signing was deployed in a number of different roles in the opening months of the season, but it is only now, with the Frenchman on the left of a midfield three as he was at former club Juventus, that he is performing to his best.

Paul Pogba gives Manchester United the lead against Crystal Palace

In each of United's last three games, Pogba has had more touches and made more passes than any of his team-mates. The 23-year-old is relishing his box-to-box role in the familiar 4-3-3 formation, and his influence is all-encompassing. "He has an unbelievable shot, he can head the ball, he can combine and create," said Ander Herrera recently. "He can change the game in a second."

He did that twice against Crystal Palace last week, latching onto Ibrahimovic's knock-down to score the opening goal before setting up the Swede's winner with a perfectly weighted reverse pass. Pogba has found his feet and United are feeling the benefits.

Carrick's impact

United's recent resurgence coincides with Michael Carrick's introduction to the team. The 35-year-old had to wait until November for his first Premier League start, but he has arguably been even more important than Ibrahimovic and Pogba since then. In fact, he's the man who has provided the platform for United's A-listers to live up to their billing.

Carrick's contribution tends to fly under the radar, but his former team-mate Rio Ferdinand provided an intriguing insight into what it's like to play alongside him in his latest column for The Sunday Times.

Michael Carrick applauds Manchester United fans at the Hawthorns

"As well as the experience and know-how of where to be, he had the ability to listen to instructions," said Ferdinand. "I'd shout 'left' 'right', 'up' and 'back' - simple information - and without turning round he would take a step to the right place. He would intercept and close gaps and when he got the ball he would quickly turn defence into attack."

Carrick may not have the physical dynamism of his midfield partners Pogba and Herrera, but his intelligence has sped up their play. Carrick to Pogba has been United's top passing combination in each of the last two games, and it is no coincidence that United are unbeaten in the 12 games Carrick has started this season. Without him, their record is dismal.

Manchester United with and without Michael Carrick - 2016/17 2016/17 P W D L Win % With Carrick 12 10 2 0 83% Without Carrick 15 6 4 5 40%

Ferdinand went on to explain how Carrick sees passes before other players, and his praise was echoed by Gary Neville and Graeme Souness on Super Sunday. "Carrick has made a big difference," said Neville. "In that position, I think there are very few players who come anywhere near him," added Souness.

Defensive improvement

Carrick has provided a formidable shield for United's back four, but their defenders also deserve a share of the credit. Manchester United supporters would have scoffed at the thought of Marcos Rojo and Phil Jones marshalling their backline at the start of the season, but the duo have become unlikely heroes.

Since they came together in the midst of an injury crisis at the start of November, United have not conceded more than a single goal in a game once. And in the recent wins over Tottenham and West Brom, their steely performances were vital in helping Mourinho's side keep clean sheets.

Phil Jones and Marcos Rojo have impressed for United in recent weeks

Rojo's two-footed tackles against Everton and Crystal Palace show he is still prone to moments of recklessness, but Mourinho has defended his aggressive style and hailed his performances as "phenomenal".

Rojo and Jones are not without their faults, but they are among the Premier League's top 10 players for clearances per 90 minutes, and that uncompromising, no-nonsense approach to defending is exactly what Mourinho needed. Eric Bailly and Chris Smalling have their work cut out to get back into the team.

Team spirit

Mourinho stepped close to the mark with some of the criticism of his players earlier this season, but now that his side is beginning to meet his standards, his efforts to galvanize the squad have been notable. He dedicated the win over Spurs to the under-fire Marouane Fellaini, and he has dished out public praise to a number of individuals in recent weeks.

Paul Pogba and Zlatan Ibrahimovic celebrate at Selhurst Park

According to Neville, a man who knows a thing or two about what it takes to be successful at Manchester United, the improving team spirit in Mourinho's side has been an important factor.

"I think momentum is building," Neville said on Super Sunday. "You could see them celebrating together after the game, it feels like there is a spirit developing. What I'm seeing at the moment is more Manchester United-like. The profile of the player is better. It's taken a little bit of time to settle down, but they've got personality, strength and character."

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