Concern surfaced Tuesday, when McCarthy was scratched from his start because of soreness in his throwing shoulder, which has landed the pitcher on the disabled list in four of the past five seasons. And while Saturday's outing will truly dictate where he stands, McCarthy called Thursday's session "a little bit of a relief, considering how the week started."
"I didn't feel anything today," he said. "I felt fine, and it's really not a concern at this point. I wasn't mentally hung up, wasn't worried about it. I pretty much knew what to expect, and unless something unexpected happened, I wasn't going to be surprised. It went the way I wanted it to, and it just leaves me perfectly on course for Saturday.
"I know these next couple of starts will be big for me, to see where it's at and if it is coming on. But the way it feels right now, there's nothing that should stop me."
The A's hope not. McCarthy, pitching from the No. 1 spot, has been extremely consistent this year, allowing no more than two earned runs in six of his seven starts. He's pitched into the seventh inning in five of them, all the while compiling a 2.96 ERA.
McCarthy will be pitching on nine days' rest come Saturday, and when asked if he believed if the extra time off might affect him, he replied, "postgame Saturday, we'll find out."
McCarthy also reiterated that the pain he experienced after his last start in Boston "wasn't even pain."
"You know when you get a tickle in your throat before you're sick and you're trying to convince yourself you're not sick and two hours later you're sick?" he said. "It's like that, where it's not the actual sickness. You just feel something that feels different, and every time I've felt that, it's gone into that. But I've never been proactive with it before, so it might be possible to get around it this time.
"Everything I do is based around staying healthy, staying strong. There's not much more I can do."