Efficiency

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Great article on fivethirtyeight.com about Messi and his work rate during the World Cup.

tl;dr: -  He wasn't tired; he ran the least compared to all other outfield players (!!) but his production was still excellent. The data supports it, but anecdotally all you need to know is Argentina scored 8 goals in total, and Messi scored four and assisted on two more. Without him they don't even make it past the round of 16, and maybe not even out of their group.