How is advancement to the next tier calculated?

[simp1et0n]

I win against people in my league (Clever). From what you said, it seems that I need to play against players in the gifted league before I can advance. However, I have been starting a lot of league games and I keep getting players from my league . I have a friend who started later than me and has much fewers wins but he's now promoted to Gifted. He said he won a little over 50% of his games, but he had quite a few games where he was assigned to play with players in the gifted league.

How is assignment calculated? Is there any way to ask to play with players in a higher league?