ST. LOUIS -- Finding himself with an unplanned off-day on Tuesday, Cardinals manager Mike Shildt decided to spend the extra time digging deeper into the numbers. His purpose? To see if he could pinpoint how a club that ran out to a 20-10 start had dropped 13 of 17 games since.

Shildt maintains that he was encouraged by what he found – proof of things like an increasing hard-hit rate by the offense, high success controlling the running game and top-of-the-league defensive metrics – even if the results didn’t reflect much of a reward.

But amid a skid that’s now brought them all the way back to .500 following an 8-2 loss to the Royals in Game 1 of Wednesday’s doubleheader at Busch Stadium, there has also arrived a crossroads the club can’t sidestep for much longer.

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The question that faces the Cardinals now: How much longer will the status quo suffice?

“Listen, we’re always going to evaluate our team,” an impassioned Shildt said after the team’s afternoon defeat. “I can’t say there won’t be a change. I can’t say there is going to be a change. Literally, I’ve been off the field for three minutes. I can tell you what I won’t do right now is pin anything that’s going on on one particular person.”

His latter reference was specifically in defense of Michael Wacha, whose grip on a rotation spot appears to be loosening with each uneven start.

But he’s not alone.

Things have been remarkably static so far, with Shildt deploying the same five starting pitchers and avoiding any major shakeup to the lineup during a run that dropped them from first to fourth in the National League Central in an 11-day span. But that offense has now scored two or fewer runs in nine of its last 18 games, and the rotation remains unreliable.

On Wednesday, Royals starter Brad Keller, who was winless since April 12, held the Cardinals to two hits (both singles) over seven innings. The team’s first hit with a runner in scoring position didn’t come until the eighth inning. Three leadoff walks over the first four innings went to waste.

Then there was another ragged start from Wacha, whose 6.94 ERA over his last seven starts underscores the right-hander’s continuing struggles. His average fastball velocity remains down from years past, and his walk rate (5.6 per 9 IP) represents a career high.

He issued three more free passes (one intentional) on Wednesday while also allowing seven hits and seven runs (six earned) over 4 2/3 innings to a team that had dropped six of its previous eight games. Jorge Soler’s three-run homer during a six-run third was especially deflating.

“The way I’ve been pitching, it’s unacceptable,” Wacha said, when asked whether he felt he was pitching to stay in the rotation. “I know I have to be able to pitch better because right now … I don’t know. It’s a tough spot. You’ve got to be able to pitch well to stay in this league, and right now, I’ve not been pitching well. I’m going to have to do a better job.”

How long the Cardinals can stick with Wacha, who maintains that he’s not physically compromised, remains a topic of conversation outside the organization, as well as within it.

“We have to look at it,” Shildt acknowledged. “I don’t want to be knee-jerk right now, but we can’t continue to just … in total … something’s got to change. I can’t alibi it. I’ve got sound reason [for staying the course]. The reality is we’re not getting it done right now. And ultimately, it’s a group that we’ll all take ownership, but I’ve got to take ownership, too. I have to figure out something, and I have to lead better, evidently.”

In the short term, the club could use upcoming off-days on Thursday and Monday to skip Wacha the next time through the rotation. A longer-term solution would likely require the Cardinals to call on Daniel Ponce de Leon, Jake Woodford or Alex Reyes, who could be a ready option after he starts for Class A Advanced Palm Beach on Thursday.

While the Cardinals consider their options, Shildt will continue taking those numbers he poured over on Tuesday and impress upon his players that they forecast an about turn for the team.

“You will not find lack of optimism in this clubhouse or with me,” Shildt said. “You’re not going to find it. Not with the group we’ve got. So if I’m going to get dinged for being optimistic with this group, fire away. But I’m not going to throw this group anywhere close to a bus. I’ll get thrown at it before anyone else.

“Look, we get it. Something has to be different. We have to figure out a way to be different. We will. But as far as optimism goes, it’s not blind. The challenge, the pessimism, would be if we had a group that didn’t care, had a group that didn’t show up ready to compete, a group that didn’t throw it out there every day. You don’t see that.”