Clemens left his last start with a stiff back, but the back did not bother him yesterday.
Pettitte (6-4) had to leave his start July 26 against Arizona after five innings.
Johnson left his last start against the Royals on Monday trailing by 5-1 with one out in the second.
He left his next start with tightness in his left shoulder and had surgery later that month.
Santana left yesterday's start after four innings with a cramp in his right leg.
Karstens, who left Sunday's start with stiffness, could avoid the disabled list.
Brown left his start on Wednesday in the fifth inning because of back spasms.
"I didn't want to go back to the beginning," said Mussina, who left his start on Wednesday after 43 pitches.
Brown, who had disk surgery two years ago, left his start on June 9 with a stiff lower back.
He had to leave his last start, on Monday, after five innings because of a groin injury.