CINCINNATI -- The Cardinals had no answers for Nick Castellanos on Wednesday in the nightcap of their day-night seven-inning doubleheader.

Castellanos connected for home runs in each of the first two innings off J.A. Happ, including an eventful grand slam in the second, and drove in Cincinnati’s first six runs in a 12-2 rout of the Cardinals before 10,892 at Great American Ball Park. The Reds, who snapped a four-game skid, also received homers from Kyle Farmer and Eugenio Suárez to move 2 1/2 games ahead of St. Louis and Philadelphia for the second National League Wild Card spot.

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Paul Goldschmidt homered twice and drove in three runs in the day game to lead the Cardinals to a 5-4 win over the Reds. Génesis Cabrera threw two innings of relief to record the win as St. Louis settled for a split of the doubleheader while taking two of three in the series.

Following Castellanos’ grand slam to left-center in the second game, Cardinals manager Mike Shildt came out to speak to the umpires about examining the bat, which Shildt thought may have been chipped before his at-bat. As it turned out, Castellanos had given the bat to a fan before the bat was available to be legally examined by the umpiring crew.

The four umpires convened and then approached the Reds' dugout to discuss with Castellanos and manager David Bell and request the bat be inspected. The bat, which was retrieved, was looked over and given back to Castellanos before being returned to the young fan.

The umpires on the field, led by crew chief Phil Cuzzi, then came to the review headset at Shildt's request to confirm the standards of rules 3.02 and 6.03(a)(5), both pertaining to a legal bat and its use in game conditions.

Rule 3.02 states "The bat shall be a smooth, round stick not more than 2.61 inches in diameter at the thickest part and not more than 42 inches in length. The bat shall be one piece of solid wood."

Specifically, in 6.03(a)(5), “A batter shall be deemed to have used or attempted to use an illegal bat if he brings such a bat into the batter’s box" -- and the batter can be called out.

“The bat was chipped. It’s just by rule,” Shildt explained afterward. “Look, I don’t want to make it a big deal. The guy hit a homer with the chipped bat, so good for him. Put two good swings on it. Really wasn’t going to say anything initially, but the bat was ran out there so quickly. I didn’t want the bat to get gone. I knew there really wasn’t any recourse.”

There was one incident during the review that came to the mind of many involved.

“If you think back to the George Brett scenario (the Pine Tar game in 1983), initially they called him out, but they end up reversing it,” Shildt continued. “So, that’s what Phil said. I thought the crew handled it well. Just wanted to make sure we captured the bat because he went out there so quickly. It’s really just a safety issue with a cracked bat, but he put a good swing on it and had a couple good swings and that was it. Nothing bigger than that.”

The crew conferred with New York and confirmed they were within their discretion to allow the previous play (grand slam) to remain unchanged as it was determined that nothing on the bat affected the outcome of the contact. The umpires then had the bat removed -- it was given back to the fan -- from further use for safety reasons.

"It didn’t give him any advantage," Cuzzi said. "It’s really just more of a dangerous thing because it’s easier for that bat, if he gets a ball off the end of the bat, it could shatter and who knows? It goes in somebody’s eyes, in somebody’s face. It was more of a safety thing, but it had nothing to do with the home run. The home run was never in question about not counting it."

“My view is that was my second homer and I drove in six. All of a sudden, there was an issue,” Castellanos said. “There was no issue when [Jon] Lester absolutely carved me up. And there was no issue in the first game. But then there was an issue.”

How long had he been using the chipped bat?

“My last at-bat in Miami [on Sunday] was when I cued that slider over to first,” Castellanos added. “I just pushed the wood back. What I do -- I’ve been doing it all year because I don’t want to just waste a bat -- I will just pick the pieces of wood that are pushed back until the entire bat is intact. Then I just go and use it. Actually my Opening Day homer against them had a chunk missing because the same thing happened in Spring Training.”

The damage to the bat wasn’t as bad as it was to Happ (8-7) and the Cardinals, who were denied in their pursuit of their first doubleheader sweep in Cincinnati since June 28, 1959, at Crosley Field and their first three-game road sweep of the Reds since Sept. 19-21, 2017.

Happ was tagged for seven runs and eight hits over just one-plus inning, as his ERA rose to 6.20. Wednesday night marked the fourth time this season Happ has allowed seven or more runs in a start.

“I felt alright coming into it,” Happ said. “I guess give them credit. It seemed like when I made a mistake, they capitalized. Even when I felt like I executed, they were able to sort of hit it where we weren’t. It’s certainly frustrating after getting the first two, wanting to come in and try to set the tone for our guys and certainly frustrated I wasn’t able to do that.”

Happ was staked to an early 1-0 lead, as Tommy Edman connected for his 10th homer off Cincinnati starter Sonny Gray (7-6) to open the game, the third straight game the Cardinals homered in the first inning. Gray was pitch efficient in his five innings, allowing two hits and solo homers to Edman and Nolan Arenado (No. 27) while striking out three and walking none.

But Jonathan India doubled to left off Happ in the bottom of the inning. One out later, Castellanos homered to left to stake Cincinnati to a 2-1 lead.