Benjamin Morris at FiveThirtyEight:
Even though national teams are patchwork and only play together for a handful of games each year, how Messi plays with Argentina relates to what is ultimately a fair criticism of his success: Most of it has come for FC Barcelona, a free-spending virtual all-star squad, packed with many of the world’s best players.
As the primary striker for such a juggernaut, it can be hard to detangle Messi’s goal-scoring prowess from Barcelona’s general offensive dominance. And the 2013-14 season hasn’t helped: Battling minor injuries and facing competition for touches from superstar arrival Neymar, Messi’s most recent season was slightly below par by his standards, yet Barca finished second in La Liga. (And in the seven games Messi missed, they went 6-1.) He still scored 41 goals, but that total was less than the 60 he scored the year before, and fewer than the 51 that rival Cristiano Ronaldo of Real Madrid scored en route to capturing the Ballon d’Or.
I think this criticism is fair — and I found it intriguing enough to look into the matter myself. So I gathered and organized data, crunched it, re-crunched it, and gathered more data and crunched it some more.