For the briefest moment, Cheslor Cuthbert’s return to the Royals’ 25-man roster appeared to be the solution to team’s recent malaise.

After missing a month and a half of major-league action due to a left wrist sprain, Cuthbert was recalled before Tuesday’s game against the St. Louis Cardinals and immediately penciled in at third base. He went 2 for 4 with a three-run double, giving the Royals their first lead of the I-70 series in the fourth inning.

Try as he might, Cuthbert couldn’t save the Royals.

All-Star starter Jason Vargas was unable to make it out of the fifth inning, the defense suffered a few more malfunctions and the Royals ended a six-game homestand with a 10-3 loss to the Cardinals.

“When things aren’t going good, you’re not getting breaks, and that’s part of the reason why you’re not going good,” Royals manager Ned Yost said. “We’re definitely not getting breaks, but we’re not really making our own breaks either.”

The most common denominator among the Royals’ mishaps Tuesday evening was Jorge Bonifacio. The rookie right fielder made a late jump on a ball hit by the Cardinals’ Dexter Fowler in the fifth inning, allowing it to drop over his head and dribble toward the warning track for a two-out double.

“He broke in and then went back,” Yost said. “He misplayed that ball.”

Fowler then would score on a three-run homer off the bat of Jedd Gyorko, who drilled reliever Mike Minor’s fifth pitch of the game 420 feet to left field for a 7-3 Cardinals lead.

In the seventh inning, Randal Grichuk hit a two-out single to right field with runners on first and second.

Bonifacio sailed a throw over jumping reliever Neftali Feliz, who was supposed to back up home plate but tried to cut off the play, and past catcher Drew Butera at the third base line.

A second run scored as Butera scurried after the errant throw. Grichuk then came home on a Matt Carpenter double.

The error was charged to Bonifacio, but officials after the game said that Butera might have had a play at the plate if Feliz hadn’t deflected the ball. Feliz took the error instead.

Grichuk had set the Cardinals up in the fifth inning, dooming the Royals with a leadoff home run. Three of the next four batters reached base safely, including Tommy Pham, who softly hit a ball up the first base line.

Butera went after the ball but made no play, allowing Matt Carpenter to reach third and Pham to reach first.

“That ball was more than halfway down the line. By the time he got to it, the runner was right there at the bag anyway,” Yost said. “It was just a really weird inning.”

Later, Yadier Molina, who hit a leadoff home run the previous inning, chopped a ground ball up the third base side that skipped high over the bag. It landed beyond Cuthbert, who dove into foul territory trying to trap the bases-loaded hit.

Shortstop Alcides Escobar corralled the ball just outside the infield dirt and rocketed a throw to Cuthbert at third to get the Cardinals’ Jose Martinez as he slid into the bag.

Still, two runs scored on the play. All three runs Cuthbert had driven in against the Cardinals’ Michael Wacha to give Vargas room to breathe went for naught, for Wacha allowed only two more hits and the Cardinals’ bullpen shut the Royals’ offense down.

“I feel like I just let it get away from the team right there in that fifth inning,” Vargas said. “Some weird things happened. But with Cheslor coming up big the half-inning before, there’s just got to be a stop put to that inning regardless of what happens. It’s just a frustrating one to let get away.”

Vargas was immediately replaced for Minor. The All-Star who was 12-3 with a 2.62 ERA in the first half suffered his third loss since the break. He was charged with six runs on eight hits in 4 2/3 innings.

As they dropped to 57-55, the Royals could at least take an ounce of comfort in the American League Wild Card race. The Boston Red Sox beat Tampa Bay 2-0, keeping the Royals and Rays tied for the second spot.

The Royals will try to salvage the series with the Cardinals when it relocates to Busch Stadium in St. Louis for the final two games of the set starting Wednesday.

“We were in a really good spot, had a lot of really good momentum going for us, and we’ve run into a couple of speed bumps,” said Vargas, who has only lasted more than five innings once since throwing seven frames on June 30. “But the guys in here have been through way bigger lows and way higher highs than this. I don’t think anybody is too concerned. I think we just need to get back to doing some fundamental things and getting some momentum going in our direction.”