Hernandez on a high as United host Spurs
The Mexican scored twice in last Sunday's 2-1 win at Stoke City, notched the winner in Tuesday's League Cup win over Wolverhampton Wanderers and with Rooney and now Michael Owen out injured, is expected to start alongside Dimitar Berbatov in Saturday's Premier League game against Tottenham Hotspur at Old Trafford.
"We tend to build up heroes very quickly here but the boy is justifying the praise he is getting at the moment," Ferguson said after the 22-year-old's late winner against Wolves.
"When he came on you just knew if he got a chance he would take it," added Ferguson, who bought the striker for a reported 7 million pounds before he came to global attention with his impressive performances during the World Cup.
Some observers have compared Hernandez to a young Owen but his team-mate, who has struggled to rediscover his best form after lengthy injury lay-offs, warned that the future would not always be such smooth going.
"He's young, sharp and a good finisher," said Owen. "He seems to be thriving, he's always got a smile on his face, he enjoys his football and the fans have taken to him already.
"So far, so good, but, as I know, football changes in a week. He needs to keep working hard and keep putting in those performances because at Man United that's what it demands."
United's fans will certainly expect the good times to keep rolling for one more week at least against a team they have dominated for two decades.
Spurs have not beaten United for nine years and their last win at Old Trafford pre-dated the Premier League, coming in December 1989, when Hernandez was 18 months old.
Ferguson was three years into his job as United manager for that game while Spurs, including caretakers, have gone through an incredible 18 bosses since.
United, along with Arsenal and Manchester City, are on 17 points, five behind Chelsea, who visit Blackburn Rovers on Saturday.
Champions Chelsea, having made an early exit from the League Cup, have enjoyed a rare break from midweek action which should help ease some of the minor injury problems that have dogged half the team in recent games.
Centre-back Alex is back in full training and could see some action on Saturday but midfielder Frank Lampard is still not ready to return following hernia surgery in early September.
Arsenal host West Ham United while Manchester City visit Wolves on Saturday.