Dan Quinn and several players left the Cowboys for the Commanders. Now, the rivalry is upside-down.

ASHBURN, Va. – Inside his desk at Dallas Cowboys headquarters, Dan Quinn kept a notebook. He filled it with how his former superiors went about things.

Whenever the former Cowboys defensive coordinator saw something done in a way he liked – whether it was Cowboys coach Mike McCarthy's practice scheduling methods or how the front office approached free agency – the ideas and best practices made it onto the page.

"That’s a good deal," Quinn would tell himself as he scribbled his notes.

Quinn’s defenses ranked seventh, fifth and fifth, respectively, in scoring during the three seasons he spent with the Cowboys. Dallas went 12-5 each year and won one playoff game before the Washington Commanders hired him. Sunday will mark the first time he faces the organization that took him in following his firing as head coach of the Atlanta Falcons in 2020.

“When you see something done really well, you want to take note of it,” Quinn said Wednesday. “... And so, coming into here, for me, it was more applying some of the processes on the coaching side that I could with the staff.

“I learned a lot there. … It was an incredibly valuable time for me.”

The two franchises have taken completely different paths in 2024. Both prone to distractions in their own right, the Commanders have thrived under new ownership and a first-year general manager (Adam Peters) along with Quinn – not to mention a quarterback who is the front-runner for Offensive Rookie of the Year in Jayden Daniels. Washington, which hasn't had a winning season since 2016 and has lost five of the last six matchups against Dallas, is in playoff position. Meanwhile, the Cowboys have careened to 3-7 with quarterback Dak Prescott done for the season. McCarthy seems bound to be let go this offseason, and owner Jerry Jones can’t stay out of the news. Under new coordinator Mike Zimmer, the Cowboys’ defense entered Week 12 allowing the sixth most yards per game in the NFL (365.7), and only the Carolina Panthers have surrendered more points per contest.

“I would say coverage wise, there's probably some differences,” Quinn said when asked about the differences between the defense he saw on tape this week and the one he coached the three years prior. “Mike's got a good blitz package that he's used and had been successful for a long time.”

For the former Commanders who spent time with Quinn in Dallas recently, the downswing is surprising.

"It's not good,” said defensive lineman Dorance Armstrong, who spent the first six seasons of his career with the Cowboys prior to signing with the Commanders this offseason. “I'll just say that.

“I watch here and there. Those are still my guys, for real, but I watch them and I see what's going on.”

Quinn may have taken some of those ideas he jotted down in Dallas. He definitely took some key contributors. Armstrong, defensive lineman Dante Fowler, center Tyler Biadasz, wide receiver Noah Brown and cornerback Noah Igbinoghene are the five former Cowboys players on Quinn’s first Washington roster. Defensive coordinator Joe Whitt Jr. was Dallas’ pass game coordinator/secondary coach from 2021-23.

Fowler, who fake-sparred with the backward-cap wearing Quinn as the team stretched at the start of Wednesday’s practice, knows which side of the divide he’d currently rather be on.

"It's definitely cool to be in that type of position rather than being on the other side,” said Fowler, who was in Dallas for Quinn’s final two years. “Just cool to see what Coach Quinn has just done since he came here with this team and getting a group of guys to come together and play as one. As far as the Cowboys, it's going to be really cool to play against them. I'm playing against a lot of my old friends, a lot of my old teammates. Being able to catch up with those guys and stuff like that and going and competing with them out there on the field, that'll be cool."

Quinn has been hailed a player’s coach by all corners of the Commanders locker room. Brown has seen more of that since Quinn didn’t have as much interaction with offensive players in Dallas.

“He understands how this game goes,” Brown said. “I’ve seen nothing short of that since I’ve been here. He cares a whole bunch about his players, and it shows with how he runs the program.”

The best three seasons of Armstrong’s career (21 total sacks) coincided with Quinn’s presence in Dallas. The 27-year-old was one of the few ex-Cowboys to admit he had this game circled, even if the NFC East matchup being a noted NFL rivalry may be a thing of the 20th century.

“I feel like it's one of the bigger things for me,” Armstrong said. “Every game's a big game, but obviously when you play the team you came from, you just have more urgency or something. I don't know what it is about that, but that's what it is right now for me."

Gamesmanship will be a factor this week – for both the coaching staff and the players. Armstrong said he is giving tips to his new teammates about the tendencies of players on Dallas’ offensive line (which has its share of injuries currently, potentially rendering reconnaissance moot). Quinn classified his matchup with McCarthy – whom he called “a phenomenal coach” – a chess match.

“But at the end (of the day), it's the guys executing and playing it out,” Quinn said. “And so that's a number one top of the pile, our execution, the speed at which we play.”

Washington will face Cooper Rush at quarterback and could see some of backup Trey Lance.

"Cooper's been there for a little minute, so he knows the system really good,” Fowler said. “I think he's a good quarterback. Trey Lance is really good with his legs, and he's a dynamic quarterback, as well. You don't want to go out there half-stepping against those guys because they do play good football, as well."

For Biadasz, it will be the first time he’ll be in the same game as one of his mentors, Cowboys right guard Zach Martin, but not beside him on the offensive line. A fourth-round pick in 2020, Biadasz learned how to be a professional from the future Hall of Famer and has carried it into his new routine with Washington.

“It’s been a blessing to play next to him,” Biadasz said. “Even (former Cowboys left tackle) Tyron Smith. To see great players, future Hall of Famers, just go about their routine and everything and figure out what fits for you and how to intertwine that.”

The ex-Cowboys contingent has already influenced Quinn’s tenure; for example, it was Brown who caught the game-winning Hail Mary pass against the Chicago Bears. Aside from their availability, Quinn had a reason why he wanted Biadasz, Armstrong and Fowler in the fold during Year 1 of his second shot at being a NFL coach.

“I think the line of scrimmage is a big deal,” Quinn said.

Noted.

This article originally appeared on USA TODAY: Commanders' rivalry vs. Cowboys turned upside-down thanks to Dan Quinn