The Cubs dropped their third straight game Sunday night, but the big news was the uncertain health status of Jason Heyward.

The right fielder exited after his 4th-inning at-bat and was replaced by Cameron Maybin for the remainder of the evening during the Cubs’ 7-3 loss.

After the game, manager David Ross explained Heyward was experiencing light-headedness and shortness of breath, so the Cubs sent him to the hospital to get precautionary tests.

As of Sunday night, Ross did not have an update on Heyward’s status from doctors.

“He said he felt a little light-headed after the first at-bat and just not being able to really breathe,” Ross said. “He’s not a guy that you ever have concerns about, so when he says that he’s having trouble breathing and light-headedness, just want to make sure everything’s alright.”

Heyward has been one of the team’s most valuable players this season, hitting .300 with a .415 on-base percentage and .955 OPS. He’s also continued to play stellar defense in right field and been a steadying presence in the dugout and clubhouse.

“You’ve got guys who fluctuate a little bit and you’ll have that on any team where they’re in better moods where they hit better or something like that. But I think he’s kind of the steady rock always that just stay the course of a leader who says ‘follow me’ and every day shows up same guy, whether he’s hitting or not hitting,” Jason Kipnis said of Heyward. “He works hard, so when you’re around him, you’re working a little bit harder ’cause you know he is too.

“He’s one of those guys who brings people along with him and we’re hoping it’s not serious with what he’s got going on and back tomorrow. Tons of respect for him, I’m a big fan.”

Heyward’s status cast an ominous tone after a night in which the Cardinals closed the gap in the NL Central to only 1.5 games.

Kipnis hit a 2-run homer and Anthony Rizzo also went deep, but Jon Lester lasted just 3.1 innings and was charged with 5 earned runs.

The Cubs had opened up a 4.5-game lead in the division after Friday’s win. Monday marks the final head-to-head matchup between these two teams as Kyle Hendricks takes the ball at Wrigley Field.

NOTES

—Kris Bryant’s last 2 at-bats of the night were a positive sign for the former MVP and his team. After striking out looking the first 2 trips to the plate, Bryant got down in the count 0-2 in his 3rd at-bat. But he laid off three straight pitches out of the zone and eventually lined a single to right field.

He doubled in the left-center gap in his next trip to finish 2-for-4 on the evening.

—Continuing a weekend packed with roster moves, the Cubs selected the contract of left-handed pitcher Matt Dermody and added him to the Chicago bullpen Sunday afternoon. Tyson Miller was sent back down to the alternate site at South Bend after throwing 3 innings in the second game of Saturday’s doubleheader.

The Cubs signed Dermody, 30, on Aug. 6 after he turned in an impressive showing the Independent League earlier this year: 3-0, 0.52 ERA, 1.10 WHIP, 11.9 K/9.

Dermody pitched a perfect 9th inning in Sunday’s game, setting down the Cardinals’ 4-5-6 hitters in order. He struck out Paul DeJong with a 95 mph fastball and then induced a pair of groundouts in his first major-league action since 2017.

—Adbert Alzolay is going to stay in the Cubs rotation and is set to take the ball Thursday against the Reds. Alzolay was sent back to South Bend after Saturday, but he can return to the team by Thursday per the roster rules of the “29th man” for doubleheaders.

—The Brewers lost again Sunday, so they remain 4 games behind the Cubs in the division.