Manchester United legend Denis Irwin says their preseason tour of the USA will be no jolly for the players.
Irwin says given the competitiveness of the Premier League, United must be primed to hit the ground running when the season kicks off.
"Pre-season's the most important time for a player," he said. "It's the time when a player needs to get fit and get up to speed for the opening day of the season. One of the reasons the club comes to America is because the facilities are fantastic.
"The league's getting stronger, too, and the quality of players it's attracting is better. Kansas City Wizards beat United last year [on the pre-season tour] so we know the quality of football is high.
"Every year's a new challenge. Manchester City have got stronger in the last few years, Liverpool have had a quiet time recently but they've acquired some good players. And of course Chelsea and Arsenal will be in it, too. There's a challenge to win a 20th title next year."
