Whatever you might have thought was coming with this, Day One without the vital presence of injured catcher Salvador Perez looked strangely like the rest of the season compressed into a doubleheader Sunday at Kauffman Stadium.

Paralleling the last few months, it showcased a confounding series of extremes by the Royals.

That included a deflating start and a suddenly inspired rally before falling short in game one (8-7) against Seattle and delivering a game-two romp (9-1).

A little bit like a team that started the season 10-20 and has gone 46-33 since, the results left perceptions of them smack in the eye of the beholder … who really never should look away.

It’s obviously a different dynamic without Perez, who went on the 10-day disabled list and is unable to play until Aug. 15 in a best-case scenario (and out about a month in the worst case) after suffering a strained intercostal muscle on the right side of his chest

You can make a fine case he’s their most irreplaceable player — and, heck, no one even administered a Salvy Splash in his place on Sunday.

But it’s also a resilient, resourceful team without him.

And one that continues to unfurl surprises.

So at least for a day, the Royals remained slightly above neutral (57-53) by essentially standing their ground with the help of an improbable twist.

After all, it was salvaged by rookie Jakob Junis’ stellar game two start as a counterbalance to a rough outing for ace Danny Duffy, who allowed three home runs and seven runs overall in the first two innings of the opener.

“It’s a funny game sometimes,” manager Ned Yost said.

Duffy’s downfall included some curious lapses in the field that made four of those runs unearned — and made for a distressing start to a day it seemed the Royals needed to seize.

To stay in the American League Central race and strengthen their precarious claim to the second wild-card spot, the key demand now is to “cover for” Perez, as Yost put it Saturday.

That notion doesn’t merely entail just the play of Perez backup Drew Butera and rookie call-up Cam Gallagher, who was so at ease catching for Junis they may as well have been at another of the minor-league outposts at which they combined many times in the past.

It’s a team-wide challenge to draw together to produce more to compensate for the loss of Perez.

That’s not an unreasonable concept, and it’s one you see delivered upon all the time in sports.

This nucleus of Royals rose to it in 2014 when Eric Hosmer went on the disabled list with a hand injury and with the team holding the very record (56-52) it did entering Sunday.

With Hosmer sidelined, they surged into first place and ultimately to the wild-card berth that became a portal to another dimension.

If you were expecting such juice from the get-go Sunday, you were instead stunned by mental mistakes that made them appear lackadaisical.

That surprisingly started with an off-day by Duffy, who has given up seven home runs in 108 innings all season but allowed two in the first.

He yielded another in a four-run third that unraveled after his two-out, bases-empty 3-2 pitch to Jean Segura on the borderline was called a ball.

Duffy’s body language suggested he was frustrated by the call, which he acknowledged later.

Then came some uncharacteristic slapstick stuff out of one of the best defenses in baseball: After Duffy picked off Segura, poor execution and communication led to a bungled rundown.

Then Segura scored on a passed ball by Butera, who seemed confused about how the ball kicked away (off the home plate umpire) and was initially casual in chasing it down.

Next thing you know, Nelson Cruz hits a three-run homer, and it’s 7-0.

And the overreacting cynic within is wondering for a fleeting second if this team might plummet into a death spiral without Perez.

The rest of the day helped set that straight.

The Royals looked on trajectory to their 33rd comeback win of the season after Mike Moustakas hit his 31st home run to score two and cut it to 8-7 in the eighth.

It was still a waste of a game because of the self-defeating blunders.

But it also became something to push off from instead of wallow in.

In the process of clobbering the Mariners in game two, they got big production from an array of players:

Whit Merrifield hit his second home run of the day; Lorenzo Cain had his second three-hit game of the day; Hosmer went three for five with a home run, and Melky Cabrera went three for four with a three-run homer — his first since returning to the Royals late last month.

In the process, they moved a day closer to the return of Perez with many of the same flourishes that have been defining their season all along.

They will exasperate you at certain times, enough that many wanted them to hold a fire sale earlier

They will exhilarate you at others.

They may struggle without Perez, and they may compensate for his loss.

But as even mixed results on Day One without Perez remind, they will not fold — and that special resolve will keep this group intriguing for the duration.