Javier Hernandez is quickly making Manchester United fans understand why the team didn't spend big money during the summer transfer window. Hernandez came on as a substitute and scored a 90th minute winner preventing a potential embarrassing Manchester United loss to Wolverhampton in the fourth round of the Carling Cup. This game just two days after Hernandez scored twice in United's 2-1 win over Stoke City in the Premier League. 

Instead of going after big name strikers such as Spain's David Villa, or David Silva, Sir Alex Ferguson instead decided to spend 20 million pounds on Guadalajara striker Javier Hernandez. While the move left many fans scratching their head, fans are quickly starting to embrace the Mexican striker. 

Many fans did not know what to expect out of Hernandez this season, but he is quickly becoming a first choice striker for United. 

Wayne Rooney was once again expected to bear the majority of the scoring responsibilities for United once again this season. With Dimitar Berbatov failing to impress in his first two years at Old Trafford and Chicharito's contributions being unknown, it was reasonable to assume Rooney would need to carry this team once again. 

What has happened at Old Trafford no one could have predicted. Wayne Rooney has been in the middle of the worst form of his career. He has been in the headlines because of his personal life, he got into a contract dispute with United, and no one really knows what is going on with his ankle. 

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United have been rescued by the superb early play of Dimitar Berbatov, who would not stop scoring during the month of September. Unfortunately for Berbatov, he has not scored yet in October. 

But when one door closes another one opens, and Javier Hernandez has opened that door. Hernandez came on as a substitute to score an 85 minute winner in the Champions League at Valencia. Since then Hernandez has been nothing but breathtaking for United. 

Hernandez opened the scoring against West Bromwich Albion following the international break. During United's trip to Stoke, Hernandez once again opened the scoring with a brilliant back header in the first half. 

He wasn't done there. 

When it looked like United had blown another away win, Chicharito struck once again in the 86th minute to hand United the win. 

It looked as if Hernandez would be given Tuesday's Carling Cup match off, but when Wolves equalized to make it 2-2 late in the game. Hernandez came on in the 80th minute, and despite having just 10 minutes on the pitch, Hernandez made his mark. Hernandez made a great run from midfield and was picked out by Darron Gibson as he slotted home United's winner. 

Hernandez now has six goals this season for United. More impressive, he has 27 goals in 39 games during the year 2010. 

While it is unfair to compare Hernandez to "boy wonder" Wayne Rooney at this stage of his career, Hernandez is emerging as a star at Old Trafford. With Hernandez improving, it gives United to opportunity to rest Wayne Rooney, as they know they can win without him. 

While many fans were wondering what kind of contribution Javier Hernandez would make for Manchester United, he is quickly making a case to become a first choice striker for Sir Alex Ferguson, and I don't think any fans have a problem with that.