Playing wavs through primary media player via command line

I have HA set up with a Google Chromecast as my primary media player. This works with HA-generated TTS. Instead of making my RPI3 communicate with my receiver in another way, I’d like to just pipe audio through HA so everything uses the same channel. Right now I’m looking into Mycroft integration, and it seems to output its TTS to wavs which it then attempts to play. But since its default playback uses ALSA, I’d then have to hook the RPI3 to my receiver in another way, meaning I’d have to switch back and forth dependeing on whether I wanted interaction with HA, or instead wanted to interact via BT/Line-in with Mycroft. Naturally this wouldn’t be ideal.

Is there a hass invocation which, given a wav or mp3, would play it in my default media player? Note that what I’m not asking to do is to react to a trigger within a HA automation. I just want to stream audio through to my primary media device set up via HA.