Crash

Hi, I´m having problems everytime I play with yasuo. The problem start at the beggining of tjhe game, i have no problems chosing it, when the animation of the summoners start at the beggining of the game it crashes, I click just one time at the screen and a message pop out saying that the PvP.net or RIOT server has ended, so I close the game and reconnect, everything goes fine for a while and then the game crashes. I only have this problem with yasuo, I dont know why but it is anoying for me and my teamates.

Thank you for your attention hope I´ll receive an answer.