The teenage striker has earned plenty of new admirers for his fearless style of play since being promoted to the Manchester United first team under Louis van Gaal last season.
Rashford was rewarded for his fine displays with a call-up to the England squad for Euro 2016 and has continued to impress under new manager Jose Mourinho at Old Trafford.
The 18-year-old has already come up against a host of top Premier League defender despite having only made his top-flight debut last season.
However, the striker believes that Arsenal star Koscielny was the hardest opponent he has come up against in his career so far.
Asked about his toughest ever opponent, Rashford is quoted as saying by Metro: “Laurent Koscielny at Arsenal.
“He was a difficult defender to play against.”
The striker will be hoping to be involved when Manchester United travel to Liverpool in the Premier League on Monday night looking to bounce back from their 1-1 draw with Stoke.
MORE: Man United latest news
MORE: Arsenal latest news
MORE: Chelsea latest news
MORE: Liverpool latest news