#1 Lionel Messi
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Probably Barcelona's single biggest factor, the Argentine thaumaturge was at his best again this season, or may be even better than he has in the last three seasons or so. But anyways, he has his imprints all over this title.
Messi's staggering return of 34 goals - highest in the league (and Europe) by a mile - from 27 starts has contributed massively to Barcelona's fortunes. He has literally dragged this team through the thick and thin at various points this season by chipping in at crucial moments, and not to mention another 13 assists that he's racked up - also the highest.
Single-handedly, he's won 17 points for Barcelona, further accentuating just how instrumental he has been in the title race, alone.
Like a fine wine, the Blaugrana skipper seems to get better with age and has shown no signs of slowing down even while turning 32. In all competitions, he's netted 46 times and would inevitably hit the half-century mark by the time the season is drawn to a close.
So with league wrapped up, Ernesto Valverde and co. will now be eyeing Copa Del Rey and the Champions League, leaving the prospects of an unprecedented third treble very much alive. And if that indeed happens, you know who's going to have the biggest impact.