PITTSBURGH -- Jordy Mercer arrived at spring training without having to look over his shoulder or worry about his spot in the lineup for the first time in his career. That freedom allowed the shortstop to fine-tune his approach in search of a better start than the miserable April he endured in 2015.
The early returns are promising.
Polanco, who agreed to a $35 million, five-year contract earlier in the day, drew a walk from Seth Maness (0-1) with one out and made it to second on Josh Harrison's infield single. Mercer slapped a single to right for his fourth career game-ending hit.
Mercer finished with two hits and has two RBI during Pittsburgh's 2-0 start. He hit just .197 with four RBI in 18 games last April.
"I think the spring training thing really helped me out," Mercer said. "It's kind of the first time where I didn't really have to fight for position. I could work on some things and see different pitches and do some different things. It was a different spring training for me and it's bleeding into the season as well."
Harrison and David Freese had two hits each as the Pirates won despite struggling against the St. Louis bullpen. Six different Cardinals relievers combined to retire 18 straight before Maness' walk to Polanco set up the winning rally.
Mercer swung and missed at a changeup from Maness and made a promise to not get fooled again. When Maness came back with another off-speed offering, Mercer pushed it to right field and Polanco raced across the plate.
"Nothing breeds confidence like success," Pirates manager Clint Hurdle said. "In business. In life. In sport. (Mercer) had a big hit the other day, hit the ball in the gap, drove in a runner. Had two hits tonight. Good to see."
The Cardinals left 10 runners on in a 4-1 loss in the opener. They left just seven on base this time but went 1 for 12 with runners in scoring position.
"We had some strikeouts again but I thought we had a better approach at the plate today," manager Mike Matheny said. "Better execution, not necessarily, but guys taking better at-bats today."
Pittsburgh left-hander Jon Niese, acquired in an offseason trade with the New York Mets for popular second baseman Neil Walker, labored through five innings in his first start in a color other than blue and orange.
Niese gave up five runs, four earned, and five hits with one walk and seven strikeouts. The defense behind him didn't help.
Polanco took a wide route on Piscotty's shot to the gap in the fifth that turned into a triple, and Piscotty scored as Mercer threw wide to first on a grounder to shortstop by Matt Holliday, putting the Cardinals up 5-3.
St. Louis starter Michael Wacha, who won his first seven decisions in 2015 en route to his first All-Star appearance, struggled with his curveball and Pittsburgh pounced. Wacha gave up five runs, four earned, in 4 1/3 innings, leaving after four straight Pirates reached.
"I just got myself in trouble too many times and they made me pay," Wacha said.
Cardinals: St. Louis placed outfielder Tommy Pham on the 15-day disabled list with a left oblique strain he aggravated in Sunday's opener. ... Backup catcher Brayan Pena underwent surgery to repair loose cartilage in his left knee. Pena is expected to be out a month.
Pirates: Gerrit Cole's bumpy spring training appears to be behind him. The All-Star will make his first start of 2016 on Saturday in Cincinnati. Pittsburgh brought its ace along slowly after Cole dealt with rib issues in January.
Cardinals: Mike Leake will make his debut with St. Louis on Wednesday when the series wraps up. St. Louis signed Leake to a five-year, $80 million deal last December. The 28-year-old went 11-10 with a 3.70 ERA last season for Cincinnati and San Francisco.
Pirates: Juan Nicasio hopes to build off his impressive spring when he makes his first start for Pittsburgh. Nicasio beat out veteran Ryan Vogelsong for the final spot in Pittsburgh's starting rotation after pitching 15 shutout innings in Grapefruit League play. Nicasio went 1/3 with a 3.86 ERA while working out of the bullpen in 2015 for the Los Angeles Dodgers.
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