Mike Zimmer is running third in a race his old-school defensive mind would have preferred skipping out on, especially in the middle of a global pandemic.

A proud member of Bill Parcells' coaching tree, Zimmer essentially subscribes to the theory that most rookies not named Lawrence Taylor aren't to be trusted as starters.

And yet, according to Pro Football Focus, seven rookies have played a combined 1,876 defensive snaps as the Vikings (6-7) head into what's essentially a playoff game against the Bears (6-7) at U.S. Bank Stadium on Sunday.

Only two teams, per Sportradar, have more defensive snaps by rookies this season.

"Who's had more than we have?" asked Zimmer, sounding surprised he wasn't leading the league.

Carolina, sporting an NFC-worst 4-9 record, has 2,769. Jacksonville, riding a 12-game losing streak, is next at 2,263.

"Oh, yeah," Zimmer said. "I knew Carolina had a bunch, too."

He would have even more if cornerback Cameron Dantzler and defensive end D.J. Wonnum hadn't missed a combined six games because of injuries. But even as it stands now, the Vikings have 951 more rookie defensive snaps than the Bears and 1,270 more than a Packers team that clinched its second straight NFC North title last week.

"We've had to change [the defense] several times based on what they can handle and things like that," Zimmer said. "Now, it's not so much. They can handle more. At the beginning, especially not having OTAs [because of COVID-19 limitations], it was kind of trial by fire, I guess is the best way to say it."

In early November, as the Vikings were clawing back from a 1-5 start, Zimmer had an idea for how to simplify things for a defense starting two rookies at cornerback. The man whose forte is schooling defensive backs called on his assistant, Mary Redmond, to search the archives for a particular game plan Zimmer used as Cowboys defensive coordinator 17 years ago when NFL schemes weren't quite as complex as they are today.

Zimmer said he couldn't recall which game he did that for this season, only that the Vikings won.

Seventeen years ago is when Parcells handed Zimmer a rookie cornerback named Terence Newman. He started 16 games at cornerback that year and became one of Zimmer's most trusted players. He followed Zim from Dallas to Cincinnati to Minnesota and then coached under him for a season.

Other than Newman, Zimmer has never been a part of rookie cornerbacks playing this many snaps. Jeff Gladney has 762 snaps and 12 starts while Dantzler has 488 snaps and eight starts.

In 2015, Trae Waynes mostly sat behind Newman, playing 214 snaps with one start as a first-round draft pick. In 2018, another first-round draft pick, Mike Hughes, upped that total to 243 snaps and two starts before suffering a season-ending knee injury.

Overall, the 1,876 rookie defensive snaps are the most by far Zimmer has had in seven seasons as Vikings coach. The other rookie snaps belong to Wonnum (314), linebacker Troy Dye (156), cornerback Harrison Hand (90), lineman James Lynch (50) and safety Josh Metellus (16).

Meanwhile, of the Bears' 925 defensive rookie snaps, 867 of them belong to starting cornerback Jaylon Johnson. And he's played only 11 snaps in the more difficult slot position while Gladney (440), Hand (20) and Dantzler (five) have spent 465 snaps in the slot, according to Pro Football Focus.

The Packers' only home loss this season came Nov. 1 when an already young Vikings defense went into Lambeau Field and started losing players to injury. By the end of that 28-22 upset, seven rookies had played a combined 196 defensive snaps.

Against Aaron Rodgers. A corner was turned, at least to the point where the Vikings could get back into contention for the last of three NFC wild-card playoff berths.

Asked when he felt his rookies were able to eat solid foods, so to speak, Zimmer said, "I don't know exactly when it was. But I think basically it has been, 'Add a little bit here or there, tweak this.'"

Add it all up and it's been 1,876 snaps that only two other teams can say they've experienced smack dab in the middle of a global pandemic.