His success led to a test drive for independent BMW team Wiechers-Sport at the German circuit Oschersleben, having impressed enough in the test he was signed to compete in the FIA World Touring Car Championship, with the independent Wiechers-Sport BMW team for 2006.
Late in 2006 he was signed by the GR Asia SEAT Leon team and finished an impressive second in the European Touring Car Cup against the likes of works drivers Alex Zanardi and other FIA World Touring Car Championship regulars.
Like the previous year O'Brien got a late call to race for the Independent Danish Poulsen Motorsport BMW Team in the FIA European Touring Car Cup in Adria in Italy.
Even though O'Brien had not driven since his departure from GR Asia SEAT he qualified as top BMW driver and finished in 3rd place.
O'Brien enjoyed racing in Denmark and had a succsefull end to the championship finishing with two podiums and third place in the Valvoline Finale just behind series champions Jan Magnussen and Michel Nykjaer, O'Brien was representing Coca-Cola in Denmark and carried the striking livery of the Burn Energy brand on his BMW 320si.