Booker T. and the ___

MGS

This funk and R&B group from Memphis was known for hits like "Green Onions" and featured a legendary organist. Their initials stand for their full name.

This clue references the classic soul-funk band "Booker T. & the M.G.'s," where "M.G.'s" stands for Memphis Group. The answer is shortened to "MGS" by dropping the apostrophe and "the" for brevity, which is common in crosswords. If you know the band’s name, the initials make it an easy fill.