The Red Devils have won seven games from seven since the Norwegian took over from Jose Mourinho last month, including a 2-0 victory over Reading in the third round.

Next up for a rejuvenated United is a trip to the Emirates Stadium, as they come up against the only team to have won the competition more times than them.

Here, Sports Mole looks at how Solskjaer may set out his side in North London.

Possible MNU vs. ARS

Out: Marouane Fellaini (calf), Marcos Rojo (knock), Chris Smalling (foot)
Doubtful: Marcus Rashford (knee), Luke Shaw (illness)

Solskjaer is unlikely to risk Rashford as the striker, used in all seven of United's matches during this ongoing winning run - six of those starts - is carrying a knock and is also fatigued.

Alexis Sanchez's return from injury is therefore timely, with Solskjaer hinting last weekend that the Chilean forward will be handed a start against his former club.

Rather than use Sanchez through the middle, though, Romelu Lukaku is expected to get a rare start as he aims to build on a return of three goals in five matches.

Another player in line to return is Juan Mata, who has been involved in 11 goals in 10 FA Cup starts against Premier League opposition - three goals of his own and eight assists.

Shaw had to withdraw from the squad to face Brighton & Hove Albion because of illness, but he should be OK to slot back in at left-back here, though Antonio Valencia and Diogo Dalot are both on standby.

Elsewhere, Solskjaer has a big call to make in goal as Sergio Romero started against Reading but may be left out for this match, with David de Gea so often proving the difference for United in the big games.

> Click here to see how Arsenal could line up for this fixture