 He would help Pumas reach the final in which they faced Pachuca and scored the winning goal that gave Pumas the win in the second half of overtime.Barrera enjoyed his finest season in the Torneo Bicentenario 2010 scoring six goals in 13 games, though his season was cut short as he was called up to the Mexico national football team pre-World Cup training camp.On 16 July 2010 Barrera signed for West Ham United on a four-year contract, with a one-year option, for fee of £4m.