The United players are preparing to return to action as they bid to mount a challenge for the Premier League title following their fourth-placed finish in the Dutchman’s first season at the club.
Giggs was installed as Van Gaal’s assistant manager at Old Trafford last season after hanging up his playing boots.
And the former Wales international has stressed the significance of undertaking a good pre-season training routine in helping players prepare for the gruelling season ahead, suggesting that the whole of Van Gaal’s squad should look to impress him and his staff.
Giggs told United’s official website: “Young players might come on tour thinking they’ll not get many minutes but then suddenly there’ll be an injury to a senior player.
“The young player might then have a 10 or 15-minute cameo, play really well, get into the team for the next game and do really well again. So the tour is definitely an important stage for the young players to make their mark.
“I think you’ve seen a lot of players play well in pre-season and take that into the first part of the season. It’s a massive thing as an individual to get the best out of yourself. If you can get off to a good start it gives you confidence so you definitely can’t take the pre-season games lightly.
“Gone are the days when you’d play easy games – every match is tough and every stadium is sold out so you want to do well for the fans that have come to watch you.”
United, who face a play-off tie in August to secure a spot in the group stage of next season’s Champions League, fly out to the US for the beginning of their pre-season tour later this month.
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