PITTSBURGH -- There was a renewal of a blooming National League Central rivalry Friday night along the banks of the Allegheny River, where the Cardinals left the Pirates stunned last October. St. Louis shuttered PNC Park for the winter with a Game 4 National League Division Series win and rode the momentum to the World Series.
But in front of a home crowd of 23,342, the Pirates provided an early reminder that they intend to play challenger again in the Cardinals' attempt to repeat as division champions.
Pedro Alvarez served as the prime nemesis, stinging Shelby Miller with a pair of home runs before adding to the Pirates' lead with a slick sixth-inning slide. The bullpen let the game get out of hand, leaving the Cardinals with a 12-2 loss in the first of 19 games they'll play against Pittsburgh this season.
The Cardinals were also left to wonder how differently the night might have transpired had an interference call been made at a key point in the sixth.
"I don't know if you can put the whole game on that particular play," Matt Carpenter said. "But it certainly had an impact."
That inning opened with the Cardinals trailing by one after Carpenter answered three early Pittsburgh homers with a two-run blast. Alvarez pushed the Pirates' lead to 4-2 by beating out a double play, stealing second on a botched hit-and-run, and scoring on Russell Martin's single to center.
Manager Mike Matheny came out to discuss the play at the plate -- buying time for the club's video coordinator to review the play -- before deciding not to challenge.
He'd soon wish there was something he could do to change what happened next.
With Miller's night done and Randy Choate on the mound, Martin moved to third on another single. He then briefly broke toward home as Yadier Molina pump faked when Neil Walker took off to steal second. Martin, running on the infield grass, started back toward the base and moved into the path of Molina's throw, something the runner can do along the third-base line, the umpires later explained to Matheny and Molina, if he is not intentionally trying to impede the throw.
That conditional clause is what became the focus. Molina and third baseman Carpenter, both of whom saw Martin watch Molina release the ball before turning his head and altering his direction, believed there was intent to get hit.
"In my opinion, he was waiting for the ball to hit him," Molina said. "I don't get it. I don't get that rule. On the first-base side you have to [create a] straight [line while running], but on the third-base side you can move everywhere. That's tough. What else can I do?"
"He was not in the path of the ball until he realized he was in a rundown and he was out," Carpenter added. "As the ball was thrown, he pretty much ran right to where my glove was and got hit by it. I don't know what the rule is, but I thought it was obvious he was trying to get hit by it."
As the ball rolled away, Martin scored and Walker advanced another base. Matheny argued at length and eventually persuaded home-plate umpire Brian Gorman to confer with the rest of his crew. That meeting was brief and nothing was changed.
Under Major League Baseball's instant replay rules, Matheny is not able to challenge an interference call. He was also not as certain that there was intent behind Martin's chosen route back to third base.
"That is a momentum shifter if we get that out, and everything was executed right down to Yadi's throw," Matheny said. "I don't think he jumped in front of the ball or did anything like we've seen guys do where they're trying to intentionally get hit. He just changed where he was and let the ball hit him."
The evening unraveled from there. A two-run deficit turned into four before the inning ended and left Miller charged with five runs on six hits in 5 1/3 innings. Now 0-5 against the Pirates, Miller's ERA in those five starts ballooned to 5.93.
"It's not the park," Miller said. "It's not the team. I just pitched poorly today. I don't do anything differently to these guys than I do to anybody else."
He also insisted it wasn't the layoff. Miller's only outing over the previous 10 days came in a Minor League spring game.
Seth Maness, in his first appearance of the season, was later knocked around for a run and four hits. Keith Butler gave up five more, leaving the Cardinals open to questions about the strength of their middle relief corps. In four games, the bullpen has allowed 11 earned runs in 10 1/3 innings.
After having their third straight game delayed by rain (this time a one-hour and five-minute pushback), the Cardinals found themselves behind, 3-0, by the end of the fourth.
Alvarez connected on a two-strike fastball for a solo homer in the second and took a two-strike changeup into the seats in his fourth-inning at-bat. Miller was frustrated by the location of the fastball; not so much by where he threw the changeup.
"I don't know if he was sitting on it or what," Miller said, "but he must have been because he hit it good and it was right where we wanted it."
Alvarez, whose multi-homer game was the eighth of his career, has blasted the Cardinals for 13 homers and 45 RBIs in 205 career at-bats.
"He's been patient, stubborn with his approach, and it paid off for him tonight," Pirates manager Clint Hurdle said of Alvarez, who came in 1-for-15.
Travis Ishikawa went deep three batters later.
The Cardinals cut into the deficit in the fifth with their first home run by a Cardinals player in a regular-season game at PNC Park since 2012
Pirates starter Gerrit Cole otherwise worked around every other precarious position he had in his seven-inning start. That included one in the fourth inning, which opened with consecutive singles from Kolten Wong and Matt Holliday, then closed with Jhonny Peralta flying out to leave the bases full. The Cardinals finished the game 0-for-7 with runners in scoring position.
"You can't say enough about how good that lineup is," Cole said. "I'm glad I was able to get this one under my belt."
Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, and follow her on Twitter @LangoschMLB. This story was not subject to the approval of Major League Baseball or its clubs.