Lionel Messi drew a blank again against Bolivia as the Argentine goal machine struggled with the rigours of playing at high altitude.

The forward, who has scored 51 goals for Barcelona this season and two goals behind Diego Maradona in Argentina's all-time scoring list, was reportedly sick on the pitch during half-time as he struggled in the thin air of La Paz, more than 13,000 feet above sea level.

Team-mate Angel Di Maria had to be given oxygen on the pitch during the 1-1 draw.