Closer Bobby Parnell's next bullpen session will wait further.

Parnell, returning from surgery to address a herniated disk in his neck, injured his left quadriceps muscle covering first base during a drill Thursday. He was not outdoors with teammates for Friday's morning stretching, but pitching coach Dan Warthen said: "Everyone thinks it's very, very mild. He wanted to throw today."

Parnell, trying to be cautious, threw a 35-pitch bullpen session Tuesday. He had been listed to throw again Thursday, but decided to wait an extra day to be safe as he returns from surgery. Now, that will be delayed slightly further.