LONDON, Aug 12 (Reuters) -- Manchester United completed its third signing of the offseason after securing a deal for striker Bebe from Portuguese club Vitoria de Guimaraes.

United's website said the 20-year-old had agreed personal terms and would undergo a medical later this week.

Manager Alex Ferguson has been keen to bolster his striking options and Bebe joins along with Mexico's Javier Hernandez, who scored in United's 3-1 defeat of Chelsea in the Community Shield at Wembley on Sunday.

The 6-foot-3 Bebe is rated as one of the top young talents in Portugal and will join compatriot Nani at Old Trafford.

United begin their Premier League campaign against promoted Newcastle United on Monday.

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