Dansby Swanson has been a mainstay in the middle of the Cubs’ lineup over the last three seasons.

This season, he’s struggled when hitting in the heart of the order, and acknowledged as much following Tuesday’s loss in St. Louis.

“Yeah, I mean, really all year I’ve been pretty bad at it, to be honest,” Swanson told reporters following Tuesday’s game. “I think a lot of it is just being able to simplify and just focus on hitting the ball hard somewhere, and good things will be able to happen. Not really holding my end of the bargain up right now in that regard, and it’s definitely something that frustrates me and I gotta be better with.”

Swanson’s numbers this season when hitting with runners on base compared to hitting with the bases empty are drastic.

With the bases empty, Swanson is hitting .279 with 12 home runs. When runners are on base, his average drops to .175 with only two home runs.

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The Cubs shortstop is specifically struggling with runners in scoring position. Among hitters who have 75 plate appearances with RISP, Swanson’s .141 batting average is the lowest in baseball, with the next closest being Vinny Pasquantino of the Royals at .204.

Swanson’s struggles with men on base and RISP hasn’t always been the case. His first two seasons in Chicago saw productive numbers in those situations, producing a .252 average with runners on base and a .257 average with RISP.

With the two runners on, including the go-ahead run on second base, in the top of the ninth inning Tuesday, Swanson grounded out to Nolan Arenado to end the game as the Cubs’ lead in the NL Central dwindled to 2.5 games.

“We put some pressure on them in the ninth,” Swanson said. “We just weren’t able to get it done.”

The Cubs have lost five of their last six games, but not all of it falls on Swanson. They’ve allowed 20 home runs over that stretch and have had miscues on the defensive side of the ball as well.

Matthew Boyd gets the ball on Wednesday in St. Louis as the Cubs look to return to their winning ways.