ST. LOUIS -- J.T. Realmuto provided some of the Phillies’ biggest postseason moments last October, hitting an inside-the-park home run in Game 4 of the NLDS and a 10th-inning home run in Game 1 of the World Series.

He hopes to create more moments like that next month.

But Realmuto has not been himself at the plate this season, including Sunday’s 6-5 loss to the Cardinals at Busch Stadium. He is batting .248 with 18 home runs, 56 RBIs and a .755 OPS in 2023. He has not finished the season hitting .259 or lower since his first full season in the big leagues in 2015. He has not finished the season with a .771 OPS or lower since 2016.

“I just haven’t been able to find a groove for a consistent amount of time like I usually do,” Realmuto said. “I’m kind of fighting things back and forth. I haven’t really gotten on a roll, and hitting is a mentality and a confidence thing just as much as anything else, and I haven’t been able to find my confidence for a consistent amount of time this year.

“Confidence comes when you get hits and barrel the ball up. I feel like, even when I’ve felt good at the plate, I’ve had a lot of hard outs. I just haven’t been able to build off that.”

• Games remaining (13): at ATL (3), vs. NYM (4), vs. PIT (3), at NYM (3)
• Standings update: The Phillies (81-68) hold a 3-game lead over the D-backs (79-72) for the top NL Wild Card spot.

The Phillies are positioned to win the No. 1 NL Wild Card, even without Realmuto swinging his best. They have a three-game lead over the Cubs with 13 games to play. Even if the Phils stumble to a 6-7 finish, they will have 87 wins. The Cubs would then need to finish 10-3 to pass them in the standings because the Phils own a tiebreaker.

Realmuto hopes the Phillies finish much stronger than that, so they can enter the postseason with momentum.

He hopes the same for himself, too.

“I’ve just got to get more consistent and put the barrel on the ball more often,” he said.

Realmuto has a big leg kick, which always seems to get mentioned whenever he’s in a funk.

“It’s never that,” he said. “When I’ve been at my best, my leg kick has been at its highest. My leg kick changes at-bat to at-bat, swing to swing. It’s more of a rhythm thing than anything for me. That’s not the issue.”

While he searches offensively, Realmuto will try to shepherd a pitching staff that is struggling. Sunday, he caught right-hander Taijuan Walker, who allowed five runs in seven innings. Walker’s velocity was below his season average, but he threw more strikes, which everybody considered a positive development.

Walker entered Sunday throwing 60.3 percent first-pitch strikes, which ranked 41st out of 51 qualified pitchers. In his past six starts before Sunday, that has gone up slightly to 60.4 percent first-pitch strikes with a 5.73 ERA.

Walker threw 22 out of 30 (73.3 percent) first-pitch strikes on Sunday.

“That was the game plan,” Walker said. “I had J.T. sitting middle and I just attacked the zone. I tried to get ahead as much as possible. I got 0-2, 1-2, and tried to give myself a shot to get a swing and miss, and if not, just put the ball in play. Obviously, the numbers don’t look good, but I feel like I pitched better than what it showed.”

“Most of his problems this year have come from walks and falling behind in the count, so we tried to attack the zone a little bit more, and I thought he did a good job of that,” Realmuto said.

The Phillies tied the game in the eighth only to have Seranthony Domínguez allow a go-ahead home run to Jordan Walker in the bottom of the inning. It was the third homer Domínguez has allowed in his past five appearances.

“It wasn’t one of Ser’s best sinkers,” Realmuto said. “I think his stuff has gotten better. Definitely his slider because his last outing, it was the best I’ve seen in a couple months.”

The Phillies still had a chance in the ninth. They had runners on first and second with one out, but Realmuto struck out swinging on three pitches. Johan Rojas flew out to center to end it.

Realmuto is batting .190 with runners in scoring position this season. He batted .279 in those spots over the past two years.

“If I had the answer, I’d probably fix it,” Realmuto said. “I don’t know, maybe trying to do too much in those situations, expanding the zone a little bit. I don’t know. I don’t really have an answer for it.”