While the Cincinnati Reds were hoping to continue their playoff push against the last-place Chicago Cubs, manager Dale Sveum's club played the role of spoiler in the opener of this three-game set.
Another victory, though, could be hard to come by for Chicago, which hasn't posted back-to-back wins over Cincinnati in almost two years.
The Reds try to avoid consecutive home losses for the first time in well over a month as these NL Centrals rivals meet again Tuesday night.
Cincinnati (82-63) had won four straight overall and 22 of 26 against Chicago (61-82) before falling 2-0 on Monday. The Reds went 0 for 10 with runners in scoring position, dropping one game behind Pittsburgh for the wild-card lead and two in back of division-leading St. Louis.
"We've been rolling and winning some ballgames," said losing pitcher Bronson Arroyo, who was outdueled by Travis Wood. "It was just a hard-fought game where you don't feel you pitched that bad, the guy on the other side just does a little better job than you."
Ryan Sweeney and Luis Valbuena both homered for the Cubs, who despite Monday's win are an NL-worst 13-27 since July 29. They haven't pulled out consecutive victories over Cincinnati since Sept. 7-12, 2011, while the Reds haven't dropped two in a row at home since July 21 and Aug. 2.
Chicago could have its hands full against rookie Tony Cingrani (7-3, 2.80 ERA). After missing two weeks with a strained lower back, Cingrani allowed two runs in 5 1-3 innings to beat St. Louis 6-2 on Thursday.
"Just getting out there and throwing it and getting that same torque on my back and that adrenaline, it was good," he told MLB's official website. "It felt pretty good to get back out there."
Cingrani also came up big at the plate, going 1 for 2 with a run scored and a stolen base. He is 7 for 28 with four runs on the season.
"Love him to death, man," third baseman Todd Frazier said of Cingrani. "I love his energy, I love his poise out there. I'm very happy with what he did, and he's healthy."
The left-hander has recorded a 3.60 ERA and a .182 opponents' batting average while going 1-0 in three starts against Chicago. He surrendered two runs over seven innings in a 12-2 road victory June 11.
Cingrani has held Starlin Castro hitless in nine at-bats, and Darwin Barney and Welington Castillo are both 0 for 7. Castro, hitless in his last 15 at-bats, is 11 for 71 (.155) against the Reds this year.
The Cubs give the ball to Edwin Jackson (7-15, 4.91), the league leader in losses. He is on the verge of a career-worst 16th defeat after going 0-4 with a 5.88 ERA in his last six starts.
The right-hander held Miami scoreless through four innings before giving up three runs in the fifth last Tuesday in a 6-2 loss.
"It's definitely been a disappointing season," he said. "But every lesson is a lesson learned. You either accept it and be complacent with it or you find ways to keep working harder and get ready to bounce back."
Jackson gave up four runs in five innings in a 7-4 loss to Cincinnati on May 5.
While Shin-Soo Choo is 10 for 25 with three doubles in their matchups, Jay Bruce and Ryan Ludwick are a combined 3 for 22. Zack Cozart, who is 0 for 6 against Jackson, is batting .382 during a career-high 14-game hitting streak.