#2 David Beckham (LA Galaxy)
An obvious choice, Beckham might not have played as well as the others on this list, but his services to the MLS have been immense. HIs move from Real Madrid to LA Galaxy made news headlines around the world, not just in football circles. Interest in the league grew massively, merely from one player joining.
On the pitch, things didn't start as well though, and LA Galaxy fans were frustrated with the Englishman's decision to return to Europe on loan twice to AC Milan, labelling him a fraud.
Beckham turned it around swiftly, playing his part in two MLS Cup wins, scoring seven goals in the 2012 triumph, and providing plentiful assists. He left the club at 36, with much goodwill and his reputation intact.