CBS lead NFL broadcasters Jim Nantz and Tony Romo (John Paul Filo/CBS)

NEW YORK — On one of Jim Nantz’s favorite days of the year — NFL schedule release day — the longtime CBS broadcaster stumbled upon a pleasant surprise: In Week 7, he would be at FedEx Field with the Washington Redskins and Dallas Cowboys.

The chance to call an NFC East rivalry game is a novelty for Nantz because Fox owns the broadcast rights to the NFC, while CBS has the AFC package.

“I can’t even contain my excitement,” Nantz said this week. “It’ll be 9,065 days since the last time I did it.”

Indeed, Sunday’s game offers Nantz a bit of nostalgia. He called his previous Redskins-Cowboys game Dec. 26, 1993, in Dallas. Washington’s Chip Lohmiller kicked a short field goal to open the scoring; the Cowboys then scored 38 unanswered points. A few weeks later, Dallas won the Super Bowl.

That occasion, though, was bittersweet for Nantz. He saw the star-powered Cowboys of Troy Aikman, Emmitt Smith and Michael Irvin run over the Mark Rypien-quarterbacked Redskins just a few days after Fox outbid CBS for the rights to broadcast the NFC. CBS, a charter TV partner of the league, was losing the NFL, and a pall hung over the broadcast booth.

“We were on a countdown,” Nantz said. “We were going to lose this fairest gem — the NFL — that we had helped nurture from birth.”

The Redskins-Cowboys rivalry ended up back on CBS this weekend through a scheduling quirk called “cross-flexing.” Each year, a handful of games are reassigned from their expected network for two reasons: to balance the AFC and NFC television packages, and to maximize exposure for particularly appealing matchups.

To understand how “cross-flexing” works, you have to start with the built-in imbalance between the NFC and AFC. Fox and CBS broadcast the same number of games annually, but their packages are not created equal. The NFC features prominent teams in big markets such as the Cowboys, Chicago Bears and San Francisco 49ers, giving it an inherent ratings advantage. That is reflected in the price of the deals: CBS pays $1 billion per year for the AFC, while Fox pays $1.1 billion for the NFC.

Still, the NFL attempts to maximize all of its TV windows for all of its networks. The league introduced flexible scheduling in 2006 for “Sunday Night Football,” an effort to ensure prime-time games would not be duds. When the league was negotiating its new TV deal in 2011, there were discussions about eliminating the conference-specific packages, but Fox wanted to hold on to its NFC rights. Part of the compromise was the introduction of “cross-flexing,” which moves some attractive games from Fox to the CBS late-afternoon window — where they can get national exposure — while moving an equal number of games back to Fox. The new deal took effect in 2014.

When the NFL was building this year’s schedule, expectations for the Redskins and Cowboys were middling. Their matchup wasn’t strong enough to make Fox’s late-afternoon national window, which often features matchups between teams such as the New Orleans Saints and Los Angeles Rams or the Cowboys and Philadelphia Eagles — “A games,” in TV parlance. (“Cross-flexing” can occur before or during the season.)

Instead of reaching around 20 percent of the country at 1 p.m. on Fox, the NFL moved Sunday’s Cowboys-Redskins game to the late-afternoon window on CBS. Sunday’s game will be seen by around 80 percent of the country. Something similar happened earlier this season, too, when the Saints and New York Giants, two NFC teams, met on CBS.

Nantz will be on the call Sunday with his broadcast partner, former Cowboys quarterback Tony Romo, but there will be another tie to the 1993 game. Cowboys Coach Jason Garrett was the backup to Aikman, who threw two touchdown passes that day. Aikman, of course, is now a broadcaster on Fox.

Nantz called that 1993 game with Randy Cross, but his best memories are the moments surrounding it. He spent time with an ailing grandmother beforehand in Houston and had a belated Christmas dinner afterward with pro golfer Fred Couples, a friend.

Jim Nantz in 1997, four years after his last Redskins-Cowboys broadcast (CBS)

There were no first-down lines on the broadcast then, no super slow motion replays, no coaches' challenges.

“It really was half a lifetime ago,” Nantz said.

Asked whether he will discuss the 1993 game in his opening monologue, Nantz chuckled.

“People care about the game,” he said, “more than they care about me.”

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