im not masters but i know what im talking about, and have a good overall understanding of the game. if you dropped 700 sr i wouldnt blame teamates id look at your own personal preformance. because its generally 75% your fault that there is a loss( not just yours your team in general but did your mistakes contribute to the loss etc.) like is running winston ideal, do you have good enough dps/heals to support you on what your doing? if not you may need to switch or etc because winston is a verry team centered tank