After years as a starter under Andy Reid, Jackson was jarred to find himself floating up and down the depth chart in offseason practices. He subsequently jumped on Michael Vick's party line, urging Kelly to pick a No. 1 quarterback sooner than later.
Jackson eventually came around on Kelly's unorthodox practice habits, but he still agrees with Vick's desire to see a passer named by camp -- even if that won't happen.
"I do agree with it, especially when it's at training camp," Jackson told "The Rich Eisen Podcast" this week. "You know, throughout the whole offseason, I understand what (Kelly) was doing as far as him coming in, and he's not (showing) favoritism on any players, he doesn't care who's been the guy, who's been the starters ... Like I said, at the end of the day, you got to go earn your spot. He's not giving it to anybody, and if you're not going out there, you know, working hard and putting in time on the field, he doesn't really care ... he's going to treat everyone the same way, and he's going to make people earn it.
"So, right now, with the quarterback position, they've been battling. Honestly, I think they've been going at it pretty tough. So, right now, we don't know who the starter is."
So -- brass tacks -- does Jackson have a preference?
"I could care less, honestly. For real," he said. "Vick does a great job and (Nick) Foles does a great job. So, at the end of the day, man, whoever's going to get that ball in the hands where it needs to go, that's all that matters."
Jackson is learning that whatever credit he piled up under Reid quickly has become mist. Jackson's starting over again, along with Vick, to prove that he's right for what the Eagles plan to do tomorrow, not yesterday. Set to make a mountain of money after a less-than-stellar season in 2012, D-Jax is under plenty of pressure to prove he belongs long-term.
Follow Marc Sessler on Twitter @MarcSesslerNFL.