ST. LOUIS -- Sometimes, Reds starter Sonny Gray will have the one bad inning. Sometimes, Gray will get little or no run support. And indeed there have been games, like Sunday’s 5-2 loss to the Cardinals, during which both issues contributed.

Gray allowed two runs and three hits -- all in the bottom of the fourth -- while pitching five innings with two walks and five strikeouts. Despite his 3.64 ERA, he is 0-4 in his six starts.

"I got zero swings-and-misses on breaking balls,” Gray said. “That's normally my best pitch. I didn't have it today. It was just OK."

According to Statcast, Gray threw 21 curveballs with seven called strikes, one foul ball and one ball put into play -- but not a whiff. It’s a pitch he throws 23 percent of the time, but it hasn’t been a friend as much this season.

Entering the day, opponents had batted .350 against his curve. They hit .232 against it last season with the Yankees.

If Sunday’s outing had a familiar look, you’re right.

• On April 5 during a 2-0 loss to the Pirates, Gray had six scoreless innings and a stretch of 16 consecutive hitters retired. That ended with a Starling Marte single and a wild pitch eventually led to a curveball left over the plate that Jung-Ho Kang hit for an RBI double and the go-ahead run.

• On April 17 vs. the Dodgers during a 3-2 loss, Gray allowed one hit over five innings and retired 12 in a row until he opened the sixth with a leadoff walk. After a two-out intentional walk, A.J. Pollock saw a well-located curveball but still lifted it for a three-run homer and the game.

• On Tuesday vs. the Braves, Gray had a 3-1 lead in the sixth inning when bad luck befell him, and he allowed three runs and the lead. But Cincinnati staged a comeback for the 7-6 win.

Having retired 10 of the first 11 Cardinals with no hits, Gray appeared to be coasting into the fourth inning when St. Louis perked up. Paul DeJong hit a one-out double and Marcell Ozuna walked before Jose Martinez hit an RBI single into right field. Yadier Molina added a sacrifice fly to right field to score Ozuna and that was all the Cardinals really needed.

“He did a good job, considering, against that lineup,” Reds manager David Bell said. “If you’re not hitting on all cylinders, they’re going to get you. It happened all in one inning. But to his credit, he knows himself well. Between now and his next start, I’m sure he’s very aware of what he needs to do to get that back. Over the course of the year, some days you don’t have all your pitches.”

Gray, who threw 90 pitches overall, also tried his slider but got no swings and misses and five foul balls. He also offered two changeups that were fouled off. He didn’t give up on his curveball, either.

“Everything I was throwing was kind of yanked,” Gray said. “You've just got to stay with it and kind of make some stuff up in the last innings and just try to get through as long as you can."

Cardinals starter Jack Flaherty scattered four hits -- all singles -- in his seven innings. Joey Votto was the only Reds player who reached second base, in the top of the first, until Jesse Winker doubled to lead off the ninth. Two runs scored when Scott Schebler hit a two-out double down the right-field line to snap an 0-for-19 stretch.

Cincinnati dropped two of three games in the series at Busch Stadium.