OWINGS MILLS, Md. (AP) Instead of playing football, Joe Flacco is playing the waiting game while his back heals.
The Baltimore Ravens quarterback missed the first two days of training camp, and there's no telling when he will suit up.
Coach John Harbaugh said it might be a week, and Flacco agreed after his teammates walked off the field Friday.
''That's what we're all hoping for,'' said Flacco, now in his 10th NFL season. ''I want to be out there as soon as possible.''
Backup Ryan Mallett ran the first team, and the Ravens signed quarterback David Olson on Friday.
Olson played under Harbaugh's brother, Jim, at Stanford. He transferred to Clemson for his senior season and most recently played in the Champions Indoor Football League.
''We had to have another quarterback to get through practice and get through reps,'' John Harbaugh said.
Harbaugh brought up the possibility of signing free agent Colin Kaepernick on Thursday. Whether that happens might depend on Flacco's status.
''It has to do with our need,'' the coach said. ''Joe's day-to-day. Do we really have to make that move or not? That's the decision that really has to be made.''
Flacco insists his time on the sideline will be limited.
''I feel great. I can honestly say that,'' he said. ''It's so early in camp that it's kind of useless to push through and maybe hurt yourself even more. ''
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