CHICAGO -- The Cardinals tested the Cubs' pitching all day on Sunday, but the biggest at-bat may have come in the eighth inning when Chicago manager Joe Maddon made it tough on reliever Brian Duensing.
The Cubs led, 4-3, after Jason Heyward's tiebreaking RBI single in the seventh. Duensing took over in the eighth and with two outs, walked Kolten Wong, then gave up a single to Randal Grichuk. Maddon chose to intentionally walk pinch-hitter Stephen Piscotty so Duensing would have to face Matt Carpenter.
"Going by our work, Duensing is a really good matchup on Carpenter," Maddon said, referring to the Cubs' scouting reports. "I did not want to run away from that matchup. Before the play occurred, I thought, 'If this guy hits a double and second and third, first base open ... we'll walk the guy and pitch to Carpenter.' ... I've got Mr. [Jeremy] Greenhouse in my back pocket, so I chose to walk him."
Greenhouse is the Cubs' assistant director of research and development, and one of the so-called "geeks" who provides Maddon with numbers regarding batter-pitcher matchups to help with the lineups, situations. Perhaps they should call him "the baseball whisperer."
What was Duensing's take on the at-bat?
"I felt like the way Carpenter swung at the slider, I thought he was kind of on it a little bit or knew it was coming, and I didn't like it," Duensing said of his approach. "We changed the signs and we started off first-pitch fastball middle, then fastball away, slider, and we got to 1-2 and switched it up and went changeup. We got him to swing over the top of it."
Carpenter struck out, and the inning was over.

The bullpen was busy on Sunday.
C.J. Edwards struck out Grichuk to end the sixth and strand two, and Pedro Strop escaped a two-on, one-out jam in the seventh, ending that by getting Jose Martinez to ground out to first.
"I think we've been feeding off each other a little bit, especially today," Duensing said. "Today was a high-emotion-type game. We fed off each other well. That's a big win."
"Duensing has had a great year," Maddon said of the lefty. "He's been on a roll every month but maybe April. He's really the guy. I'm good with him on righties. Look at the numbers."
Duensing is holding right-handed hitters to a .211 average, while lefties are hitting .258.
The Cubs held on for a 4-3 win to complete a sweep of the Cardinals and maintain a four-game lead over the Brewers in the National League Central, while the Cardinals dropped to six games back.
Most important: Chicago's bullpen did not allow a run over nine innings in the three-game series.

It wasn't all pretty. Duensing slipped off the mound after he struck out Carpenter, which closer Wade Davis was quick to point out.
"I almost fell after the pitch," Duensing said. "I didn't go down. I stayed up. That's the most important thing. My spike got caught and I was off balance. I was too fired up, I guess."
It's that time of year.