ST. LOUIS -- Lacking their closer in a pivotal division game with two weeks left in the season, the Cardinals blew a late lead in their 7-6 loss to the Brewers on Sunday afternoon at Busch Stadium.

John Gant walked three of the first four batters he faced to start the ninth inning to load the bases. After lefty Tyler Webb got Mike Moustakas to fly out in shallow center field, rookie reliever Junior Fernandez entered the game and was tagged with the highest-leverage situation of his Major League career: bases loaded, two outs, a one-run lead in the ninth inning against former National League MVP Ryan Braun.

Fernandez gave up a grand slam.

The defeat cut the National League Central-leading Cardinals’ lead to two games ahead of the Cubs and three over the Brewers. The Cardinals were leading the division by 4 1/2 games at the beginning of the weekend before two losses to the Brewers.

• Box score

There were a multitude of reasons that led to the Cardinals’ defeat -- which saw Michael Wacha throw five scoreless innings -- starting with closer Carlos Martinez’s absence and the decisions that led to Gant, Webb and Fernandez pitching in the ninth inning.

Where was Martinez?

Martinez spent Saturday night in the hospital with respiratory issues that began when he got sick while the team was in Colorado earlier in the week. Those issues continued when Martinez began to warm up during Saturday’s game. He sat himself down during the warmup, manager Mike Shildt said.

Martinez is no longer in the hospital, but he did not come to Busch Stadium on Sunday.

“We’re trying to figure out, whether it’s [an] allergy or respiratory [problem], exactly what it is,” Shildt said. “We’re hopeful he’s day to day.”

It’s unclear when Martinez might be back.

“I’m more concerned about Carlos and his health,” Shildt said. “Last night, I was with him a while, and he was laboring. I just want to make sure he’s OK and we’re getting out of the woods with him from a medical standpoint. Then we’ll take care of the baseball after that.”

Why not save Gallegos for the ninth?

After lefty Genesis Cabrera threw a scoreless sixth inning, he allowed a single to Eric Thames to lead off the seventh. So right-hander Ryan Helsley was brought in to face Lorenzo Cain with the Cardinals leading by one. Helsley -- who hadn’t given up a run in 10 innings (five outings) since Aug. 20 -- got Cain out but allowed a go-ahead two-run homer to the left-handed-hitting Cory Spangenberg and two singles after that.

Shildt brought in Giovanny Gallegos to face the top of the Brewers order.

“Gio was a consideration to finish the game, as well, but at that point, you have to manage the game with what you see,” Shildt said. “We have to keep it there. So, we keep it there, and it went from there. He did his job, got out of the seventh.”

The Cardinals got the lead back in the bottom of the seventh with home runs from Paul DeJong and Harrison Bader -- who notched his first career multihomer game. The two-run lead meant the eighth inning belonged to Andrew Miller, with the left-handed hitting Moustakas and Thames due up.

An error in right-center field after Bader and Dexter Fowler let a routine fly ball drop led to an unearned run, but Miller got out of the eighth with the Cardinals still ahead, 4-3.

Gallegos and Miller pitched in the highest-leverage situations of the game at that point against the heart of the Brewers’ lineup.

What went wrong for Gant?

Gant came into the game with a 10-0 record and 3.09 ERA with three saves this season. On Saturday night, he needed 11 pitches to strike out the side. The Cardinals felt confident in his ability to protect the lead, and rightfully so.

In 22 pitches on Sunday, Gant walked Ben Gamel and Travis Shaw, got Trent Grisham to strike out looking and then issued another free pass to Yasmani Grandal to load the bases.

Asked what wasn’t working for him on Sunday, Gant simply said, “Command.”

“He just couldn’t command the ball,” Shildt said. “Maybe a little rushed. I’m not really sure. Made some pitches, just not enough quality pitches. Behind in counts, and part of that is you’ve got a one-run game and you want to make sure you’re being careful. You get to be too careful, and you get a lot of traffic out there.”

Gant didn’t think he was trying to be overly precise.

“I’m just trying to get outs, man,” he said. “That’s about it.”

What about Brebbia?

After Webb got the second out of the ninth, experienced right-hander John Brebbia could have taken the reins instead of the rookie Fernandez, but Shildt wanted to avoid him because he had been used in three of the previous four days.

“Could have gone to Brebbia for there, but he’s thrown a fair amount of pitches,” Shildt said. “He clearly would have answered the bell, but we liked fresh, good stuff on Braun.”

That fresh arm was the 22-year-old Fernandez, who threw just 12 pitches Saturday night and got three swinging strikes. Fernandez, whose season started with Class A Advanced Palm Beach, has pitched in eight Major League games this year, and in one of those appearances, he faced Braun in a similar situation: On Aug. 21, Fernandez struck Braun out swinging with the bases loaded.

This time, Braun hit a 3-2 slider, the seventh pitch of the at-bat, 433 feet into center field.

“It didn’t break,” Fernandez said. “It stayed right in the middle.

“I like the challenge. You want to come in, get that out, win the game. But unfortunately, I didn’t get it, it didn’t happen and I have to be better next time.”