On Wednesday, Del Rio admitted the apparent: The Raiders' production cratered after an offseason switch from Bill Musgrave to Downing.
"Well, obviously, a lot of things have gone on in a negative direction," he said, via the team's official website. "But I do know the guy is super bright. He's going to be a really good coach in this league. I believe in him. Those are not things that people want to hear right now because the reality is we've underperformed offensively this year. So naturally there's going to be those kinds of questions. I think we all understand that. I understand it. He understands it."
Whether you read that as a small vote of confidence or Del Rio being kind to a man he plans to fire likely depends on your bend.
What isn't debatable is the Raiders' offensive struggles this season. Oakland went from No. 6 in total yards per game (373.3) and No. 7 in points (416) in 2016 to No. 19 in yards (323.3) and No. 23 in points (291) in 2017.
Del Rio made the offseason switch from Musgrave to Downing in order to keep the younger coach from getting an OC gig elsewhere. The decision had a decidedly negative effect on the disappointing organization.
Part of the struggles could be blamed on Derek Carr's back injury suffered in Week 4, but the quarterback didn't look comfortable even before that hindrance occurred. Carr, who supported Downing, has been plagued by poor decisions and been gun-shy to pull the trigger on downfield throws.
Downing's scheme has been criticized for its simplistic route concepts and the head-scratching decision to take a powerful offensive line and ask them to run stretch-zones, rendering Marshawn Lynch and the run game mostly impotent.
Given the systematic problems this season, another OC switch could be coming soon for Del Rio -- if owner Mark Davis doesn't decide to wipe out the entire coaching staff after Sunday's season finale.