With the bases loaded and two outs in the fourth inning Monday night, Paul DeJong took one slider for a ball, swung through another and fouled off a sinker before taking two balls for a full count. Before the next pitch, the Cardinals' shortstop took a deep breath and relaxed.

When Reds starter Anthony DeSclafani threw a sinker down the middle, DeJong pounced -- and deposited it behind the center-field wall at Great American Ball Park.

DeJong’s grand slam was the exclamation point on the Cardinals’ 7-5 win in the series opener against the Reds. Navigating his way back after missing more than three weeks due to a positive COVID-19 test, DeJong has begun to heat up at the plate.

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After a three-hit game Sunday, DeJong launched his first career grand slam 409 feet to straightaway center. It extended the Cardinals’ lead -- which they had built with a run in each of the first three innings -- -- and gave them needed insurance when Eugenio Suárez hit a three-run homer in the ninth off Jake Woodford to cut the Reds’ deficit to two.

“I was on deck and [backup catcher Andrew] Knizner said, ‘Hit this ball straightaway,’ so he kind of locked me into my direction right there,” DeJong said. “And I just got a 3-2 fastball I could handle. Didn’t try to do too much, and it ended up being a big difference in the game.”

Cardinals starter Dakota Hudson earned his first win of the season, allowing two runs (one earned) in seven innings, striking out seven and walking none. The right-hander worked around two singles in the first inning and allowed the second run in the sixth, but otherwise had the Reds fooled. Hudson struck out the side in the third, getting the final swinging strike from each batter on a different pitch.

“It’s just me recognizing quality hitters that I’m facing and having a complete arsenal as a starter, rather than just being out there trying to overpower guys,” Hudson said.

With the Cardinals standing pat at Monday’s Trade Deadline, the current roster is the one they have heading into the last month of the season. And if they want to make a push for the postseason -- and the National League Central title -- the offense will have to step up.

The last two days have shown what that offense can do. On Monday, Paul Goldschmidt was on base five times -- the 21st time he has done that in his career and second with the Cardinals -- and was part of three of St. Louis’ four scoring frames. He doubled in the first run, scored the third run after being hit by a pitch and took a two-out walk two batters ahead of DeJong’s grand slam.

It’s clear that Goldschmidt is essential to the offense, but DeJong is crucial to the middle of the order. In the past two games, DeJong has batted in the fifth spot, with Goldschmidt and the left-handed-hitting Brad Miller ahead of him. Both are leading the team in walks -- Goldschmidt with 22 and Miller with 15 -- which is what they did in the fourth inning to load the bases for DeJong.

“Both Goldy and Miller are disciplined guys,” manager Mike Shildt said. “‘This is what the game’s giving me.’ Want to do damage, want to take good swings. But [if it’s] not around the plate, we’re going to let the next guy do damage. It’s a good team approach. It works.”

Last season, DeJong had 30 home runs, a single-season franchise record for a shortstop. Only one of those came with runners in scoring position. DeJong hit .193 in such situations, and that lack of production drove him to work on his mentality when he came to the plate with runners on base. He took advice from Goldschmidt and former teammate Marcell Ozuna, who told him to simplify and be stubborn about getting a pitch to hit instead of chasing around the zone. And DeJong worked on breathing exercises to calm his anxiety. That’s why he took a deep breath with a full count in the fourth.

Entering Monday, DeJong was hitting .429 with runners in scoring position. Monday was his 14th game of the season, and the grand slam was his second home run of the year -- and first with runners in scoring position.

“It’s really just been controlling my mind,” DeJong said. “I really like where I’m at right now just being balanced, strong in my legs, not trying to do too much. We work great as an offensive group when we put at-bats together, and I happened to be the guy up with 3-2, bases loaded, two outs. Just a great opportunity there. But when we work together, big hits will come.”