The Athletic Bilbao midfielder sealed a £29m switch to Old Trafford earlier this month, before England international Shaw swapped the south coast for Manchester after completing a £27m move last week.
De Gea was voted United’s player of the year last season as the Spain shot stopper shone during a torrid campaign, marking three years at the club in style.
And the 23-year-old reckons Herrera and Shaw will be left staggered by the reception United receive during the summer tour of the United States of America.
“I have a very nice memory of my first moments on tour with United,” De Gea told Manchester Evening News.
“I remember vividly meeting the players and the first training sessions with them and Sir Alex. It was a truly unforgettable experience.
“The tour helps you learn to live and train with great footballers such as the ones at this club.
“It is such a big club and you realise how big it is when you travel abroad to countries like the United States and Japan. The club has such a huge fanbase.”
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