The 21 year-old Mexico international signed for United yesterday in a shock deal.
Hernandez was at Old Trafford on Wednesday night to watch the Champions League quarter-final with Bayern Munich.
While he was disappointed at the outcome, he marvelled at the atmosphere, which he hopes to experience for himself next term.
Before that, Hernandez must secure a place in Mexico's World Cup squad, which he is tipped to do.
And that will confirm a quick return to England as Mexico will tackle Fabio Capello's men at Wembley on May 24.
"I hope to be at the World Cup," he said. "I have to work hard to win a place in the national team, then I might get a chance to play against England."