Alexander-Arnold will be making his 100th Liverpool appearance if he takes to the field in the Premier League game against Aston Villa this weekend.
However, on the 21-year-old’s 15th outing for the club, he was pitted against Rashford on the right wing in a Premier League game at Old Trafford in March 2018.
By the time Alexander-Arnold came to grips with what he was up against, Rashford had already scored twice in a 2-1 win.
Rashford ran Alexander-Arnold rugged before Jurgen Klopp put the latter out of his misery by substituting him with ten minutes to play.
Alexander-Arnold has since come up against some of the very best in world football, including Lionel Messi and Cristiano Ronaldo, but has chosen Rashford as his toughest opponent after initially underrating his national teammate.
"[That match against United was] the toughest in terms of a direct opponent and someone getting on top of me in professional football. I'd say I underestimated him," Alexander-Arnold said of Rashford to The Athletic.
"It was a massive learning curve for me. It was something that I hated happening. As a Liverpool player it's probably the worst game of the season to perform like that. But when things like that happen you have to learn from them.
"It was a wake-up call. You hate days like that. You don't want to experience that. You remember how it felt and that makes you try everything you possibly can to ensure you don't have another one like it."
Alexander-Arnold has featured 14 times for Liverpool this season, scoring one goal and providing two assists.
