Manchester United continued their Europa League quest with a dramatic 2-1 win over Rangers on Thursday night - and they were given a helping hand along the way.

An own goal from former United loanee Jack Butland, who punched the ball into his own net, opened the scoring at Old Trafford before chaotic scenes unfolded at the end - with Ruben Amorim's side prevailing.

Matthijs de Ligt saw a goal ruled out by VAR in the first half - despite one or two question marks on that decision - yet it mattered little in the grand scheme of things after 90-plus minutes.

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Bruno Fernandes grabbed the winner in stoppage time. That after Cyriel Dessers had threatened to spoil the night.

United still have work to do to book their place in the knockout stages. However, they can perhaps afford to have one eye beyond the league phase as we take a closer look when the last-16 matches will take place;

How does new Europa League format work?

While the top eight sides in the league phase qualify automatically for the round of 16, the clubs finishing in ninth to 24th place kick off the knockout stages. They compete in a two-legged knockout phase play-off to secure their path to the last 16.

After four wins and three draws, United hold 15 points with three still up for grabs. They now sit fourth spot in the league phase, two points above ninth-placed Galatasaray. Mathematically, United require all three points to guarantee a fast-tracked spot in the round of 16 - anything less on their travels to FCSB, formerly FC Steaua București, could see them slip out of the top eight.

In doing so, Ruben Amorim's side would square off against one of the clubs ranked 17th - 26th in the final league standings.

When do the play-off ties take place?

The knockout phase play-offs are played over two weeks with the first leg held on February 13 and the return fixture on February 20. UEFA will confirm the calendar, including match dates and kick-off times, on the evening of the draw.

United face an already congested February and the addition of two Europa League fixtures would take the total of matches to seven across three competitions.

Crystal Palace and Leicester City travel to Old Trafford on February 2 and 7, respectively - with the latter fixture being the FA Cup fourth round tie. The first Europa League play-off would be played on the 13th before Amorim's side travel to London to face Spurs on February 16.

The second European play-off would take place four days later, on February 20, before another trip away, this time to Everton on February 22.

United would round off a challenging month by hosting Ipswich Town on February 26.

What about the following knock-out matches?

The round of 16 ties will kick off in the first two weeks of March.