We're sending positive thoughts and best wishes to onetime Stooges sax player Steve Mackay (pictured holding sax above), who has been hospitalized and is in critical condition in Daly City, Calif.

According to KQED, Mackay is being treated for sepsis, a complication of an infection that can cause multiple organs to fail. The musician's family members have been by his side in the Daly City hospital ICU.

"Our thoughts and prayers go out to Steve and [his wife] Patti for the best possible outcome," offered Stooges guitarist James Williamson in a statement. "Steve was always an important part of our band's live sound, and last year I worked with him again when he played on a couple of songs on my solo album. His expression was always unique. It was all his own."

Mackay appeared on the band's 1970 disc Fun House and later returned to the Stooges for their 2007 Ready to Die and 2013 The Weirdness albums. Mackay and Iggy Pop are the only two members still living from the band's 1970 Fun House lineup.

In addition to the Stooges, Mackay has played with the Violent Femmes, Commander Cody and a number of Bay Area-based acts.

See the Yearbook Photos of Iggy Pop + Other Rockers

See Iggy Pop + More in These 10 Rebellious TV Performances

More From The Basin's Classic Rock