HENDERSON, Nev. -- More than a few eyebrows were raised when quarterback Aidan O'Connell, a fourth-round draft pick this past April, showed up for his first day with the Las Vegas Raiders wearing a jersey adorned with the No. 4.
After all, that was the numeral worn for nine years by the franchise's all-time leading passer, the polarizing Derek Carr, who now plays for the New Orleans Saints after an awkward exit from Las Vegas.
"Yeah, it was the number that was given to me," said O'Connell, who wore No. 16 at Purdue, during training camp. "I really don't care what number I play with. I'll play with any number. So I don't worry too much about that."
Forgive Raiders fans, then, if they experience a sense of déjà vu Sunday, when O'Connell makes his first regular-season career start at Allegiant Stadium against the New York Giants (4:25 p.m. ET, Fox).
Indeed, it's a fresh start for the Raiders, who fired general manager Dave Ziegler, coach Josh McDaniels and offensive coordinator Mick Lombardi and benched starting QB Jimmy Garoppolo this week. They replaced them with interims Champ Kelly, Antonio Pierce and Bo Hardegree, respectively, and inserted O'Connell as the starting quarterback.
That Hardegree, who has only called plays in NFL exhibitions, and O'Connell, who started the Raiders' Week 4 loss at the Los Angeles Chargers, embark upon their respective futures together is, as Hardegree said, "exciting."
After all, Hardegree, who will call plays from the field, was the Raiders quarterback coach before this week's promotion.
"He's the coach I've spent the most time with here," O'Connell said. "He obviously runs our position meetings and then I'm with him a lot extra. He's been awesome for me ever since I got here in OTAs and rookie minicamp. He's been super helpful in coaching me, teaching me, correcting me, all the things that I've needed. So, super excited for him as well and the opportunity for him."
Hardegree, meanwhile, played quarterback in college at Tennessee from 2004 to 2007 and has since coached at Duke and LSU before moving to the NFL with the Denver Broncos, Chicago Bears, Miami Dolphins, New York Jets and New England Patriots before coming to Las Vegas with McDaniels last season.
The challenge, then, is tweaking an offense that is No. 31 in the NFL in total yards and is 30th in points scored per game. Especially by a playcaller who has yet to call plays in a regular-season game for a rookie quarterback with two career appearances.
"Changes [to the playbook] would be a difficult thing; it's a short time," Hardegree said. "The important thing is our players, and we just have to execute better, and I've got to give them the ability to do that. ... I trust all those guys and I've got to put them in a good situation. And I really believe it's all about execution, and the answer is sitting in those chairs in there."
Hardegree, 39, was referring to the Raiders players in general, O'Connell in particular.
O'Connell started when Garoppolo was out with a concussion and came on in relief of Brian Hoyer in the Week 7 loss at the Bears when Garoppolo was sidelined with a back injury, completing 65.4% of his passes (34-of-52) for 313 yards, a touchdown pass and two interceptions. He has a passer rating of 72.0, a Total QBR of 7.6, and has also been sacked seven times and lost two of three fumbles.
"I think the experience is super valuable," O'Connell said. "I think the game reps are priceless and I definitely learned a lot and I've got to take what I learned and try to apply it to practice. And, again, it's also now a different challenge and different team we're going against. So, at the same time you can reflect on it, but you've got to take the challenge as it comes."
He has the support of teammates.
"Aidan is just a really consistent dude," said All-Pro receiver Davante Adams, who has been targeted 13 times and caught eight passes for 75 yards from O'Connell. "You look at him when we're watching tape -- we're watching it from the end zone copy -- whether Jimmy or Brian is in there, literally, simultaneously, he's doing [it]. Whether they're handing the ball off or faking and going into play pass or whatever, you see him just working on his craft and just always ready for his opportunity.
"So, having that type of mentality as a young guy, he could obviously sit back there quietly, but the way he works on his body, all the things like that, it's a lot more mature than what I've seen from a first-year quarterback. ... So, it's a recipe for success."
Adams was also supportive of Hardegree as the playcaller.
"I don't see us reinventing our offense," said Adams, coming off a one-catch game at Detroit.
"I see us just maybe expanding on some more of our playbook and tweaking a couple of things based off what we see on tape. But for the most part, I like what we have in [the playbook] right now, and I can get behind Bo any day. He's a good, smart football mind out there, and obviously being led by Josh, you're going to learn a lot of things and be able to understand how to call the game. So, looking forward to it for him."
Feelings are mutual. No matter what number O'Connell is wearing these days. Because as he said in camp, his wearing No. 4 had nothing to do with superstition, or the number being the square root of his college No. 16.
"No, nothing like that," he laughed at the time. "I'm not that good at math."
The Raiders' interim regime is counting on him being better at football.