With Jason Campbell possibly done for the season because of a fractured collarbone, Heyward-Bey is trying to get comfortable with the player many expect to take over as Oakland's starter.
Heyward-Bey, the No. 7 overall pick in the 2009 draft, is trying to expedite the process.
"It was very important," Heyward-Bey said Thursday. "He wants to throw, we need to throw, we need to get the chemistry going so we stayed after. We stayed after with Jason, we stayed after with Kyle (Boller), so we stayed after with Carson just to get better."
Palmer, Boller and Terrelle Pryor continued to share reps in practice, though in all likelihood, the decision will come down to Boller or Palmer.
"I ain't telling anybody anything, so you guys can all stop (asking) now," Jackson said when asked who's starting. "Everybody's an option. I mean, I could use Jacoby Ford back there if I had to. We have all kinds of different packages we could use. Anything and everything is up and available right now."
NFL Network insider Jason La Canfora cited team sources in reporting Wednesday that the Raiders plan to start Palmer.
The Associated Press contributed to this report.