The Strangers is an American country band best known as the back-up band for singer-songwriter Merle Haggard. Formed in 1965 in Bakersfield, California, United States, the band continued to tour with original co-founding member Norman Hamlet, as well as Haggard's children Dana and Ben.
The lead singer of The Strangers had other bands that he played in.
It is correct because it is stated that the strangers was his back up band, which should mean that he plays in other bands, or at least one band.