Former Arsenal defender Martin Keown has been discussing his clash with Ruud van Nistelrooy 12 years ago.
The trophy is the only chance United have of silverware this season, and with Arsenal's Champions League hopes hanging by a thread, their most realistic.
With the two sides neck and neck in the league, it's likely to be a game full of intensity, and perhaps that is understating it quite a bit.
One man who knows all about the once ferocious rivalry between the two sides is Martin Keown, the ex-Arsenal defender who was banned for three matches and fined by the FA for unsporting behaviour in the now infamous 'battle of Old Trafford' in 2003.
Keown aggressively taunted Dutch striker Ruud van Nistelrooy after he crashed a last minute penalty against the bar which saw the game end a draw, after the defender had been judged to have fouled Diego Forlan in the box.
Speaking about the incident, Keown told The Mail: "The other game people love to remind me of is the ‘Battle of Old Trafford’ in 2003. In the little black book of opposition players, Ruud van Nistelrooy was one not to be trusted.
"He was a top player and a fighter, but he would look for any reason to go down. Perhaps I overreacted, but the whole team was infuriated by him. And I’m still not convinced I deserved to give away the penalty that Ruud eventually missed!"
Keown's reputation took a battering after the incident, but the miss proved pivotal. The match took place in September of 2003, and Arsenal went onto put together an unbeaten run which saw them win the league and be crowned as the Invincibles.
Manchester United did have one positive moment over the Gunners that season, beating Arsenal 1-0 in an FA Cup semi-final at Villa Park with Paul Scholes scoring the only goal, while Van Nistelrooy would score a penalty against Arsenal a year later in a win at Old Trafford.