Three of the Cardinals' homers came against D-backs starter Ian Kennedy, whom St. Louis drafted in the 14th round of the 2003 Draft. Kennedy didn't sign and attended USC before being a first-round pick of the Yankees in 2006.
"You throw up eight in any inning against any big league team, that's pretty special -- and against a very good pitcher," manager Mike Matheny said. "[But] I didn't realized we were going to need every one of them."
The D-backs jumped out to an early 2-0 lead on three hits against Shelby Miller, but Matt Holliday erased it with a 427-foot blast to center field in the bottom half of the frame, tying the game at 2.
The tie held for two innings until the Cardinals blew it up in the fourth. Daniel Descalso started the action with a double and then slid home safely on an RBI single from Jon Jay. With one out, Kennedy fielded a grounder from Yadier Molina, but missed an opportunity for a double play at second with a wide throw. Still, Kennedy needed just one more out to escape with a one-run deficit, but instead, he opened the floodgates by walking Holliday.
With the bases loaded, Allen Craig made Kennedy pay with a two-run single. Matt Adams cleaned up the rest with a three-run home run to right field.
"It was just a bad changeup," said Kennedy, who allowed a total of 13 hits and 10 earned runs. "I had some pretty good at-bats against him before. It was just a bad pitch. It was my fault."
Kennedy walked one more and served up another dinger to Descalso before he could secure the third out on the 50th pitch of the inning. The eight-run fourth was the second-biggest inning for the Cardinals this year.
"We were having great at-bats and played a little long ball today, so that was a lot of fun," Matt Carpenter said. "It was a big win for us to split that series and get a little momentum heading into Cincinnati."
With his pitch count wildly out of control at 99 through four innings, Kennedy was removed from the game. But reliever Matt Reynolds had similar results in the fifth, when even Miller got in on the action for his first home run since high school on just the fourth hit of his career. Before his base hit in the second and his first big league homer, Miller was 0-for-22 with 16 strikeouts this season.
"It was something I'll remember for sure," Miller said. "Obviously not the best hitter in the world. Pitchers aren't, but sometimes you get lucky."
Carpenter followed Miller with a solo shot of his own to make it 12-2 with the Cardinals' second set of back-to-back home runs this season.
Meanwhile, Miller was making quick work of the Arizona offense. He retired his last seven batters, six of which were strikeouts -- four looking, two swinging.
"I was just behind in the count the first inning, and then I started settling in, getting ahead and got more comfortable out there and started making some pitches," Miller said.
Seth Maness relieved Miller for the seventh as Matheny cleared his bench. Miller allowed two runs on six hits, no walks and nine strikeouts in six innings.
Maness, who has been impressive in 13 relief appearances as a rookie, ran into trouble in the seventh, allowing four consecutive singles and three earned runs in one-third of an inning. Matheny trotted out his eighth rookie pitcher of the season in Kevin Siegrist, who struck out Didi Gregorius and Eric Hinske to end his first Major League frame.
Siegrist struck out another pair of batters in the eighth, and a fourth rookie, Keith Butler, took over in the ninth. Butler allowed the first earned run of his short career and let two more slide by, before Matheny turned to closer Edward Mujica to secure the final out.
"They just kept pounding out good at-bats," Matheny said. "They were relentless."
Siegrist was the seventh rookie to make his Major League debut with the Cardinals this season and the ninth to appear in a game. While the Cardinals rookie pitchers were taking down Arizona, the organization added two more to the pipeline with the No. 19 and No. 28 Draft picks.
"They know what they want and they know what they're looking for," Miller said. "It's a great organization to be a part of. I wouldn't want to be anywhere else or change anything on my way up. I know the guys they drafted are going to be in great shape coming up throughout the years."
After losing back-to-back games for just the second time this season, the Cardinals split the series and maintained their hold on the best record in baseball.
"In my opinion, if there's another team that's matched up with us well, those guys are up there on the top of the list," Carpenter said. "They're a really good-hitting club and they've showed it this series. You know, it was a tough series, so to split that was big for us."