Sir Alex Ferguson still intends to buy a new striker. The Manchester United manager has so far been frustrated in his attempts to add some extra firepower to his squad. Rumours were rife yesterday that Dimitar Berbatov was about to sign for the Old Trafford outfit, only for the Bulgarian to be found at Tottenham instead. Although he came on as a second-half substitute in Tottenham's defeat at Middlesbrough, the smart money is still on Berbatov being a Manchester United player before the transfer deadline closes at the end of the month, especially now Zenit St Petersburg have lowered their asking price for Spurs target Andrei Arshavin. But if it appears Ferguson is not going to get his man, the chances are he will turn elsewhere as the Scot wants to have a four-pronged strike force for the new campaign. 'We are working on bringing in another top striker,'Ferguson said. 'Having added strength up front is a situation I really enjoy. 'Ideally I like to operate with four experienced strikers, as we did when we won the treble, when we had Andy Cole, Dwight Yorke, Teddy Sheringham and Ole Gunnar Solskjaer. 'It was an admirable strength to have when it came to the end of the season and we were competing on three fronts with key games coming at us thick and fast.' Valencia's David Silva is another known favourite of Ferguson, while Thierry Henry and Klaas-Jan Huntelaar of Ajax could also come into the reckoning. However, while his efforts to bring in a new face continue, the United boss does accept he may have to work with what he has. Carlos Tevez and Wayne Rooney will lead the attack against Newcastle tomorrow, with Fraizer Campbell and England Under-19 international Danny Welbeck providing the back-up until Cristiano Ronaldo and Louis Saha return from injury or Angolan Manucho receives his work permit. 'If our plans do not come to fruition it is hardly the end of the road,' claimed Ferguson. 'We certainly will not be going backwards with the players we already have and in my view we are the boys the others will have to beat.'