Rank Play Win No Star Gained
Ensure Not Play Casual Mode.
Definitely was not a casual game. Also, when I won, a message popped up related to ~can not go below rank floor, even though had 3 stars on Diamond 5. Hearthstone is just buggy.
This could be related to the situation where people win in Arena, yet their run ends, due to a disconnect during matchmaking:
So if that happens when you play ranked, you could be essentially placed in two games at once, one you loose because of the disconnect, one which maybe you win. Once your game is won, the client checks how many stars you now have, and updates the display. In this case, you may be gaining one star from the win at the same time as loosing one for the phantom disconnected game.
Did you have any connection issues when that happened? Or, possibly, did you enter the Play queue, then abort before it found you an opponent? There may be a very small time window where the game finds you an opponent, but the client does not yet disable the Cancel button, so it could lead to the same situation.
I have not played any arena games in the past 6 months.
There was however a disconnect that did occur prior to that game as it was a 25 minute game (not an issue with my internet connection as I was browsing a web page during that time, most likely hearthstone server problems).
It is possible I clicked cancel when I was in the Play queue for that particular game as I could’ve wanted to switch to a different deck.
Odd part, was that I was not near a ‘rank floor 0 stars’ when I won, so the message displaying is definitely a bug unless say rank 4 is considered a floor to the client.