Who was the first centaur Harry Potter met?

Out of his friends he met Ron Weasley first, but the first wizard dude he met was Hagrid, when the Dursleys moved to the shack in the middle of nowhere. Although until Harry was one, he was being looked after by his parents, then Hagrid, Dumbledore and Mcgonagle took him to the Dursleys. But he can only remember meeting Hagrid on his 11th birthday in the shack.