My opponent was platinum, he only had a few games played, though. This is the third time this week that i'm matched against, and beat, a platinum player (none of them had more than 10 games played in 1v1 tho (this one had quite a few 2v2-4v4 played and is plat/diamond in all)).
I expect to get promoted to silver soon (which would be progress) since this game was 'evenly matched' and i don't even get matched against bronze players anymore (except for a few exceptions against ranked 1/2 bronze with lots of games played and likely a matchmaking rank higher than bronze).