Friday night will be a stern examination of both sets of defenders. Michael Cox provides the tactical analysis and Alan Thompson looks at the betting.
The Red Devils go into the match in fantastic form under caretaker manager Ole Gunnar Solskjaer. Creating a lot of chances and being "the protagonist team in every game" has made the side extremely happy.
At Arsenal, he was at his blockbuster best when playing through the middle, rather than on the flanks.
According to a report from the Mirror, United have a new policy against signing players over the age of 28 moving forward.
Unai Emery has a couple of selection problems, however.
Stephan Lichtsteiner is experienced but nowhere near as mobile as Bellerin, while Ainsley Maitland-Niles is definitely not a natural right-back option.
Arsenal predicted XI: Cech; Maitland-Niles, Sokratis, Koscielny, Kolasinac; Xhaka, Torreira, Guendouzi, Ramsey; Lacazette, Aubameyang. Manchester United won that match 3-1.
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The players were given no indication his future was on the line and it has come as a major shock to the dressing room. The club deliberated over his future during the past week but appeared to have settled on keeping Henry at the club.
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It has been a long road back, and the distance she has come to reach the last four in Melbourne was all a bit much for her. But Collins lost her cool when Kvitova ran away with it 7-2 and argued with the umpire at the beginning of the second set.
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Tomorrow - back to her best during what she calls her "second career" - Kvitova will play for the championship at Melbourne Park. Serena Williams was perfectly composed. "She got a little bit shaky in the end so I took my chances and I won".
"We were always the closest rivals".
Solskjaer confirmed on Thursday's press conference that Alexis Sanchez would be involved against his former club, but the Chilean is most likely to come on from the bench. His battle with Torreira could be feisty.
However, Arsenal have also suffered the aftereffects of the deal that took Sanchez to United. They might have freedom if Arsenal use a narrow diamond system, but must be careful not to open up space in the channels.
Victor Lindelof and Phil Jones are expected to pair up in defence once again on Friday night.
"He knows he can't do it by himself, it's a team game and he's a character that brings so many good things with him when he's enjoying himself, I have to say". I can see this being something of a goalfest, so I'll back over 2.5 goals at [1.7]. This game will kick off on Friday at 19:55 hrs BST. That winning run also includes an FA Cup victory as well. Arsenal put themselves back on track with a good 2-0 win over Chelsea last week and they are unbeaten at home since losing to City on the opening day of the season.
Arsenal: The Gunners already saw United this season in early December, and that game finished in a 2-2 draw.
There hasn't been a 0-0 between these two for nearly five years and I don't expect that to end here. "I think we have done that", a happy Herrera said. The midfielder revealed, "Since the first day he [Solskjaer] arrived the message has been very clear: this is Manchester United and you have to show that you are Manchester United players".