Manchester United face Rangers on Thursday night in their penultimate league phase game as they look to reach the Europa League last 16.

Ruben Amorim will be hoping for wins against both the Scottish side and upcoming FCSB to secure a fast-tracked spot in the round of 16 by finishing inside the top eight.

But, if United were to become unstuck in either game then they might have to play an extra round of knockout football before reaching the last 16 in the competition's new-fangled format.

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How does the new format work?

While the top eight sides in the league phase qualify automatically for the round of 16, the teams 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 three wins and three draws, United hold 12 points with six still up for grabs. They sit in seventh place in the league phase, a point ahead of Rangers who occupy the final automatic spot.

If United were to tumble down the table and out of the top eight, between ninth and 16th, then they would enter a draw on January 31 to determine who they face in the knockout phase play-off.

Who could United face in a knockout play-off?

With two games remaining, the league is likely to see a sleuth of changes with no side yet to be guaranteed automatic qualification.

If Amorim was to fail to gain enough points in the final outings and fall to below eighth, he would face a two-legged tie against any side who finished between 17th and 24th. As it stands, the following clubs would be potential opponents:

Viktoria Plzen

Besiktas

Porto

AZ Alkmaar

Union SG

Fenerbahce

PAOK

Midtylland

Elsewhere, Hoffenheim and Braga are among those currently residing outside a play-off spot but still hoping to make the next stage of the competition. The draw takes place at the House of European Football in Nyon, Switzerland.

United can face another English side in the knockout phase play-offs as well as opponents they met during the league phase.

When will the fixtures be played?

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.