ST. LOUIS -- If Padres fans are feeling down after their team got swept in a crucial three-game series at Busch Stadium over the weekend, all they have to do is study the team from the other dugout to gain a measure of optimism.

Things can turn on a dime at this time of year. The Padres’ 8-7 loss to the Cardinals on Sunday afternoon was St. Louis’ eighth straight win. During that stretch, the Cardinals made up five games in the National League Wild Card standings, largely at the Padres’ expense.

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Who’s to say it can’t go the other way just as quickly? Well, the schedule might, but more on that in a bit.

The loss leaves the Padres 3 1/2 games back in the race for the second NL Wild Card spot. 

“It’s not gone our way. A lot of injuries, some bad breaks in games, other teams making great plays, too,” reliever Craig Stammen said. “But one thing I know about this team is there’s no quit. It would have been easy to quit today. We’re going to continue to show up these last two weeks.”

Stammen -- as he had the last time he spoke with the media via Zoom -- predicted a Padres comeback to reach the postseason. That certainly won’t be easy with all 13 games left against the three best teams in the NL, the Giants (six games), Dodgers (three) and Braves (four) and the Padres running out of pitching options.

“This is going to make the next two weeks a little tougher than we thought they were already going to be, but we’re up for the challenge,” Stammen said. “It will be cooler when we figure it out and win this thing.”

The Padres fell behind 5-0 in the first inning after Jake Arrieta got just one out before he had to leave the game accompanied by a trainer because of a right groin strain. He told the team he was unable to push off his right leg to drive toward the plate, forcing the early hook. Coming just days after the Padres lost Blake Snell to a similar injury, Arrieta missing starts would put the club in a difficult bind simply to cover innings.

Fernando Tatis Jr. dropped a Nolan Arenado popup to open the floodgates. Tatis, making just his sixth career start in center field, still could have gotten an easy out at second or third base, but instead he came up firing to home as Tommy Edman scored easily. Tatis’ pair of misplays on that fly ball were among several the Padres made in the series while the Cardinals played nearly flawlessly in the field.

Padres manager Jayce Tingler attributed Tatis throwing to the wrong base to his inexperience in center field.

“Looking back, maybe you take the out at second,” Tingler said. “He came in ready to make a play in case they were tagging there, so that’s where his mindset was, to catch and go home, then after the ball went on the ground, he just kept going with those instincts.”

San Diego continued to chip away at the deficit for much of the game but couldn’t quite whittle it down to nothing. The Padres went 2-8 on the trip to Los Angeles, San Francisco and St. Louis, prompting Tingler to call it a, “brutal road trip.” For the Padres to stay in the race, they’ll have to be ready to contend with a 97-53 Giants team starting Tuesday that will be playing hard to hold onto its one-game NL West lead over the Dodgers.

“No doubt, it’s an uphill fight, but this is a group of guys that knows how to fight and we’re going to fight together until the end,” Tingler said.

Tommy Pham was central to the Padres’ comeback attempt Sunday, hitting a solo home run in the sixth inning and a two-run double in the eighth.

The Padres termed Arrieta’s injury, “mild,” but they don’t have much room for another blow to their pitching depth. While the team is hopeful Chris Paddack and/or Snell could come off the injured list and pitch again this season, it has signed struggling veterans Arrieta and Vince Velasquez just to field a competitive rotation. Now, they might have to resort to bullpen games every fifth day.

“From a depth standpoint, any time you lose somebody, certainly at this time of year, it’s never a good thing,” Tingler said. “We’ve got the off-day tomorrow to try to figure it out, as far as the rotation goes.”