Alvarez broke open a close game in the sixth by beating out a potential double play, followed it up with the fifth stolen base of his career then scored with a deft slide around St. Louis catcher Yadier Molina's tag that gave the Pirates the momentum they needed to pull away.
"I thought the stolen base was key," manager Clint Hurdle said. "He puts a lot of focus on running the bases and he's arguably one of our best baserunners when he's on."
It certainly looked like it, as Alvarez's outstretched left arm slid across the plate a split second before one of the game's best defensive catchers could nab him. The Cardinals imploded from there as Shelby Miller (0-1) continued to struggle against Pittsburgh.
Miller fell to 0-5 with a 5.92 ERA against the Pirates in his brief career after tying a career-high by allowing five runs in 5 1-3 innings. The right-hander is 16-5 with a 2.34 ERA in his 33 other major league appearances.
"It's not the park. It's not the team. I just pitched poorly today," Miller said. "I guess it just lines up that way where I don't pitch well when I face them."
Travis Ishikawa added his first major league home run in nearly two years for Pittsburgh. Gerrit Cole (1-0) gave up two runs in seven innings in his first start since losing the deciding Game 5 of the NL division series to St. Louis last October.
Six months removed from a taut NLDS that pushed the eventual NL champions to the brink of elimination, the Pirates sent an early message they have no plans of going away.
Cole is considered the ace in waiting after a stellar rookie season in which he was arguably Pittsburgh's best pitcher over the final six weeks. Eager to take the next step in his development, the 23-year-old kept the Cardinals in check by mixing a fastball that consistently reaches the upper 90s with improved offspeed stuff.
He also showcased some of his maturity, working out of a bases loaded situation in the fourth by getting Jhonny Peralta to fly out. His only mistake came in the fifth when Carpenter drilled a shot into the right field stands to pull the Cardinals to 3-2. Otherwise he teamed with catcher Russell Martin to keep St. Louis in check.
"I think it was just a really well-played ballgame on our part," Cole said. "I can't say enough about what Russ did behind the plate. Not sure there are any other catchers in the entire world that could handle what I threw at him tonight."
Pittsburgh's offense — which mustered all of 20 hits in 35 innings of a season-opening series against the Chicago Cubs — made sure it didn't stay close for long after pounding out 16 hits in eight innings against the NL Central favorites.
Alvarez began the year in a 1 for 15 slump but ended that with a home run to the gap in left-center for his first home run of the season. He added his second two innings later with a long drive to right-center that traveled an estimated 448 feet.
His hustle down the first-base line in the sixth allowed Pittsburgh's rally to continue and the Pirates pressed the advantage. Molina committed a rare error after Alvarez's slide, botching a potential rundown at third base when his throw hit Martin in the back and rolled into the stands. The miscue gave the Pirates a 5-2 lead and Pittsburgh poured it on in the late innings. NOTES: Ishikawa's solo home run in the fourth was his first since May 15, 2012 while playing for the New York Yankees. ... The start of the game was delayed 1:05 by rain, the third straight game a Cardinals' game was delayed by weather. ... Injured Cardinals 2B Mark Ellis is starting baseball activities but it remains uncertain when he'll be ready to return from left knee tendinitis. Ellis went on the 15-day DL on March 27 and is eligible to return on April 11. ... The series continues on Saturday. RHP Joe Kelly will make his season debut for the Cardinals against Pittsburgh's Francisco Liriano (0-0, 0.00).
Link to box score: Pittsburgh 12, St. Louis (2-2) 2
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