The Mexico international became the first signing of the summer window for the Irons in mid-August, arriving from Ajax in a £32m deal as David Moyes began life without Declan Rice.
It proved to be an eventual final few months for the 25-year-old in the Dutch capital, four years after moving there from Club America.
Chelsea attempted to sign the midfielder during the January transfer window but saw a late £43m offer rejected, while Borussia Dortmund were also interested.
Alvarez, however, has now started life at West Ham in productive fashion. Excellent against Luton before the international break, the Mexican already looks a key player under a manager not exactly renowned for throwing his new signings thrown in at the deep end.
Speaking of Dortmund’s interest, Alvarez told the Mexican National Team’s YouTube channel: “There was a little bit on the Dortmund side that was a fairly specific option, and, in the end, it couldn’t be, but well, there was a lot of rapprochements on their part, including visits to Amsterdam to meet my family.
“I have always been of the idea that things happen for a reason, that everything is perfect and good. Now I am more than happy about the step I took to join West Ham, which is a team that in one month has shown me a lot of things.
“When you reach the best league in the world, the truth is that it is something inexplicable.”