sports commentator vs sportscaster

sports commentator and sportscaster both are nouns.

Word	Noun	Adjective	Verb	Adverb
sports commentator	Yes	No	No	No
sportscaster	Yes	No	No	No

As nouns, sports commentator and sportscaster are synonyms defined as:

sports commentator and sportscaster: an announcer who reads sports news or describes sporting events

Other synonyms of sports commentator include sports announcer.

sports commentator (noun)	sportscaster (noun)
an announcer who reads sports news or describes sporting events	an announcer who reads sports news or describes sporting events