The success of football teams wearing red shirts - including Manchester United, Liverpool and Arsenal - is no coincidence, academics have revealed.
Manchester United's red strip could give them an advantage
Scientists at universities in Plymouth and Durham analysed data on all English league clubs since World War II and found home teams in red won more often.
Players in yellow or orange shirts had the worst record but performances away from home did not show any differences.
Researchers believe there could be a psychological boost in wearing red.
They said the crimson shade is often associated with male aggression and dominance.
Professor Robert Barton, from Durham University, said: "We see a couple of possible explanations.
"Firstly, over time supporters may have been subconsciously more attracted to a club wearing red, so the club has developed an increasing resource base within its community.
"Secondly, there may be a positive psychological boost from wearing red that is reflected on the field of play.
"Competing against a team in red could also impair performance."