"Whether or not he's able to pitch Saturday, that's probably in doubt, but I'm not going to rule it out to this point," manager Bob Melvin said. "We'll probably wait another day before we make an announcement on what we'll do Saturday."
Should the A's decide McCarthy isn't ready for the outing, which would mark his second straight missed start, it would make sense for Oakland to DL him, so as to be able to bring up a starter from Triple-A without making another roster move. McCarthy would be eligible to return as early as June 23.
The 28-year-old righty has missed time with the same injury on three separate occasions this season and five times in the past five seasons, including last year, when he was out for six weeks.
Right-handers Graham Godfrey and Tyson Ross are the likely go-to options in the event Oakland needs a starter in his stead Saturday.