"Yeah, especially for a quarterback," Kevin Kolb said.
Jackson injured his back and was still being evaluated, the Eagles said after practice. But about a half hour later, Jackson walked out of the locker room on his own, eased himself into his black Porsche, and sped away without comment.
His teammates and Eagles sources said the injury was minor, and the fact that Jackson walked away from the locker room suggested as much. One team source said that the pain was concentrated toward Jackson's lower back and that it was too soon to say when he could return.
Nevertheless, the scare put into perspective the old adage that "you're only a play away." It might have even more meaning for someone who stands 5-foot-10 and weighs 175 pounds, as Jackson does.
His injury highlighted an eventful day of training camp, when the full squad practiced in full pads for the first time and in front of a full house.
On a picture-perfect day, an announced training camp crowd of 8,238 was treated to the highs - and lows - that come from a young team. There were spectacular throws and dropped passes, sound collisions and missed blocks, signs of unity and plenty of fights.
But the Jackson jolt stood out for obvious reasons. With a new quarterback under center, the third-year Pro Bowl receiver is expected to be of extra importance.
"Yeah, you definitely need him out there," Kolb said.
The injury happened in the afternoon no-pads session during a seven-on-seven drill. Kolb threw to Jackson on a slant, but the ball was slightly behind the receiver, and he twisted to pull it in. Cornerback Asante Samuel was covering and linebacker Omar Gaither was converging, but there was no contact.
"I told Coach, 'I didn't touch him. I don't know what happened,' " Gaither said.