Jayden Daniels spent the week practicing in a brace. Marcus Mariota spent last Sunday throwing three touchdown passes.

Only one of them plays in London.

Dan Quinn made it official: “Jayden Daniels (elbow) is out for this weekend. Marcus Mariota getting the start.”

So Commanders vs Colts kicks off at 9:30 a.m. ET on Sunday with the backup under center, Daniels missing a second straight game with the dislocated left elbow he suffered in Week 2.

DraftKings, via CBS Sports, has the Colts -3.5, the total at 47, and the moneyline at Colts -187, Commanders +155. Prices move, and those are the numbers at the time of writing.

A spread like that reads like a vote on the quarterback who isn’t playing.

This game will be decided by the defense that is.

The Colts give up 417 yards a game. That’s 32nd. Dead last.

They give up 6.5 yards a play, the worst in the league, and 30.3 points a game. Against the run, it’s 4.9 yards a carry.

Three games. Zero interceptions.

The strange part is how tidy they are about it. Indianapolis commits the fewest penalties in the NFL, five a game. The Colts don’t hand out free yards. They just hand out the regular kind.

Washington runs for 132 yards a game, eighth in the league, and sits at plus-two in turnover differential.

ESPN’s John Keim was asked what decides it. He didn’t need long.

“I’ll say the ground game. The Colts have two outstanding corners in Sauce Gardner and Charvarius Ward to contend with Terry McLaurin and Stefon Diggs. But they rank 28th in yards per carry allowed.”

That’s the whole matchup in three sentences. Gardner and Ward can make life hard for McLaurin and Diggs on the outside. Nothing about this Colts defense says it can stop a handoff.

And Mariota is a quarterback who sometimes hands it off to himself. Since 2020 he has run for 1,068 yards at 5.7 a carry, with eight rushing touchdowns. Put a 5.7-a-carry quarterback in front of a defense allowing 4.9 a carry to everybody, and the arithmetic does the scouting.

He isn’t a caretaker throwing it two yards past the line, either. Against Seattle last week, in a win, he threw for 181 yards and three touchdowns, to Rachaad White, Treylon Burks and McLaurin, with no turnovers. His average throw traveled 8.5 yards downfield, seventh in the league.

The longer record holds up too. Since 2020: 43 games, 22 starts, 35 touchdown passes, 18 interceptions, a 91.3 rating. That’s a backup with a starter’s paperwork.

Now, the history. Yahoo’s preview asked it straight: “Can the Colts beat Mariota for a 6th time?”

On paper it’s a fair question. As a Titans starter from 2015 to 2019, Mariota went 2-5 against Indianapolis, with nine touchdowns, six interceptions and a 90.4 passer rating.

But look at that rating. It’s 90.4 against the Colts and 91.3 since 2020. Jinxes don’t usually land within a point of a career average. That’s just Mariota being Mariota. He hasn’t seen Indianapolis since 2019, and the Colts defense he sees Sunday is giving up 6.5 yards a snap.

The part of that record worth keeping an eye on is the ball. Twenty sacks and four fumbles in those seven starts against the Colts, and 16 fumbles in 43 games since 2020. A defense with no interceptions needs somebody to give it something. If the Colts cover this number, that’s the likeliest gift.

Washington has at least had time to think about what the Colts can see. Here’s the Commanders’ David Blough:

“Over the first couple weeks, we’ve dove a lot into our own self-scout because we know there’s only three weeks of information that the Colts are getting to look at on our offense.”

Three weeks of tape makes for a thin scouting report.

Then there’s the man picking against them. Pete Prisco of CBS set the scene: “Both teams won for the first time last week and now head to London.” Both sit at 1-2. His pick is Colts 31-30.

Do the math on that one. A one-point Colts win doesn’t cover 3.5. And 31 plus 30 is 61, a full 14 points over the total of 47.

Even the man picking the Colts doesn’t have them covering.

There’s a reason he sees points. Washington’s own pass defense allows 276 yards a game, 30th in the league.

And the Commanders throw for just 182 a game themselves.

So Washington won’t win an air raid, and shouldn’t try. It should run the ball, against the worst defense in football by yards and by yards per play.

That’s why it’s close. It isn’t a reason the Colts should be laying more than a field goal.

The elbow is out. The run game isn’t.

Odds: DraftKings via CBS Sports, at the time of writing (Friday, Oct. 2), and subject to change.

Disclosure: Bounty Sports may earn a commission from sportsbooks named on this page. It does not change which numbers we quote or which side we argue.

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