6. Erasmo Ramirez
You can't talk about an underrated reliever and not mention Erasmo Ramirez. He threw quality innings after quality innings last season for Washington, a trend he hopes to continue in 2023. I thought it was essential for the Nats to bring him back this year, and they did just that. His potential most likely isn't anything better than what we saw from him last year, but that performance alone would prove to be an excellent re-signing by the Nats.