However, Carr was not revealing the entire truth, he acknowledged during a weekly Raiders Inside podcast, per NBC Sports Bay Area.
"When you break three bones in your back, it doesn't feel good," said Carr, who missed only one start after suffering a transverse process fracture in his back in Week 4 against the Denver Broncos. "Injuries will never be something I talk about, especially during the season, but since it's after the season, the (back issue) was one of those things that was there."
Carr threw for a career-best 32 scoring passes in 2015 -- his second NFL season -- and followed that up by throwing for 28 scores versus six interceptions in 2016 as Oakland clinched a playoff spot for the first time since 2016.
Following that season, Carr signed a five-year, $125 million contract and hopes were high for a run at an AFC West title. Instead, Oakland went from a 12-4 mark to a 6-10 record, ending the season with four consecutive losses.
Carr had five TD passes and zero picks in the first two games this past season but he failed to throw more than one scoring pass in eight of his final 11 starts while finishing with 13 interceptions.
"I had to deal with it," Carr said. "I had to do certain things to manage it, but I just didn't talk about it. I didn't want it to be an excuse. It was a want more than anything else. I didn't want it to be a reason. I couldn't let that be a reason why I couldn't do A, B or C."