Manchester United's unbeaten streak continued on Saturday after they soundly beat travelling Watford at Old Trafford.

The Red Devils haven't been beaten in the Premier League since October and they're now just two points behind second place. They've come a long way since being cut adrift of the top five in the table, never mind the top four.

Walter Mazzarri's side gave it a good go across the ninety minutes but United were just too strong from start to finish, never really looking like conceding and in fact looking like they could go on and score another couple against the visitors.

United, still competing in four competitions, now face a big week with UEFA Europa League and FA Cup football on the cards.

Here are FIVE lessons we learned during Saturday's win...

Juan matters to United

With four goals and two assists in his last ten appearances, it's clear that Juan Mata is as important as ever at Old Trafford.

He provides a classy and let edge in the final third, always able to find space in and around the box to either create or score himself. That was again apparent today. At one point in the first half it looked like United may never score.

However, the Spaniard popped up at the perfect time with the opportunity to slot the ball home, which he duly did with aplomb.

When he plays well it's likely that United are too and he'll be a vital part of any top four charge to come in the next few months.

Martial likes adversity

Anthony Martial cannot be denied. Spending two consecutive matches on the bench after a storming FA Cup performance, he had to be patient for his chance to impress again in the Premier League.

He took that chance confidently and convincingly. He was the catalyst for the win, his overlapping run and cross setting up Mata before combining with Zlatan Ibrahimovic in the second half to fire home United's second.

The Frenchman now has eight goals and four assists across the campaign which isn't a bad return at all, especially considering he hasn't exactly been a first team regular.

He now deserves an extended run in the team in the weeks to come, from the start, to have the chance to show he can produce magic on a consistent basis.

Mourinho is a great man manager

It's clear when you see the uptick in form of Ander Herrera, Henrikh Mkhitaryan and Anthony Martial that Jose Mourinho is a great man manager. He rewards hard work and performances, with the players seemingly respecting his tough style of leadership.

Some of the players whose United future seemed to hang in the balance are now some of the team's top performers and it's all down to the way Mourinho has nurtured them through poor form to become the players most people know they can be.

Watford lack a clinical edge

Watford didn't really perform poorly, the found themselves in decent positions in the final third but that last pass or that shot at goal just didn't come off.

Mazzarri's side lacked that clinical edge you need, especially at Old Trafford. If you find yourself with space in United's portion of the pitch then you really need to make it count.

United defended stoutly but there could be a feeling of missed opportunity in the Watford camp. Counter-attacking well, they just fell short at the vital moments of the match.

Top four contenders

There's no doubting that Manchester United are now top four contenders and that's something you wouldn't have considered just two months ago. Mourinho has them playing an exciting brand of attacking football and they don't look like losing anytime soon.

They now don't play again in the league until March with the next two weekends booked up for cup action. By the time they host Bournemouth in the Premier League on March 4th they could have silverware in the bag and have progressed in two massive competitions.

This is a crucial part of the season but if they keep winning then the potential is there to have a very special campaign in Mourinho's first year in charge.