The Reds will aim for two more victories in Tuesday's doubleheader as the clubs continue a five-game set at Great American Ball Park.
Cincinnati (46-42) is 17-8 since June 11, matching Pittsburgh for the top mark in the NL, and has won 29 of its last 38 against Chicago (38-49) dating to Aug. 10, 2012.
The run of success likely makes the uncertainly of Joey Votto easier to stomach. The 2010 NL MVP could be headed to the disabled list with a strained left thigh, though the club is waiting for Monday's test results before making a decision on its first baseman. Votto has missed the last two games, including Monday's 9-3 series-opening win.
Jay Bruce, filling in at first base, homered for a second straight game after going 0 for 21 over his previous six. He made an error in his first game at first since high school, but his manager saw enough to keep him in the infield if need be.
"I thought he did a terrific job," Bryan Price told MLB's official website. "Again, it says a lot about our guys that are willing to do what it takes to create a situation where we have a better chance to win the game."
Cubs first baseman Anthony Rizzo, meanwhile, homered for the fourth time in five games against Cincinnati.
Rizzo is batting .367 against the Reds this season, but that could be tough to keep up with All-Star Johnny Cueto on the mound for Game 1.
Cueto (8-6, 1.99 ERA) has been slightly more hittable lately, surrendering seven hits in three of his last four starts after not allowing more than six in his first 14. In Wednesday's 3-0 loss in San Diego, the right-hander gave up seven hits and three runs while striking out eight in seven innings.
He's yet to face the Cubs this season but is 4-0 with a 1.37 ERA and .185 opponent batting average over his last seven starts in the series. He's held Rizzo to 1 for 12 and Nate Schierholtz to 1 for 9.
Travis Wood (7-6, 4.62) takes the ball for the Cubs, who have scored four runs during a three-game skid.
Wood's control issues continued Wednesday as he issued four walks and allowed three runs and seven hits in 3 2-3 innings of a 16-9 win in Boston. The left-hander hasn't allowed more than three earned runs in his last six starts, but he's walked 22 batters in 34 2-3 innings since June 5, which trails only Baltimore's Ubaldo Jimenez.
In the nightcap, Chicago's Tsuyoshi Wada faces David Holmberg in a pair of season debuts.
For Wada, it's also his big-league debut with the possibility of a longer stay as the club looks to fill rotation holes after dealing Jeff Samardzija and Jason Hammel to Oakland. Wada was 9-5 with a 2.66 ERA and 105 strikeouts in 101 2-3 innings of 16 starts and one relief appearance for Triple-A Iowa.
"There's nothing that says they can't come in here and perform and help us win ballgames," manager Rick Renteria said of his new-look staff. "We're really hopeful that the guys that we have within the system will be able to come in and hopefully find a sense of comfort within that clubhouse and when they go out to the hill. Obviously, there's some nervousness that comes with the new area, the new arena. But usually those guys are able to adjust and perform."
Holmberg is scheduled for his Reds debut after going 0-4 with a 5.28 ERA in 10 starts for Triple-A Louisville. The left-hander made his major league debut a season ago with Arizona, surrendering three runs and six hits in 3 2-3 innings on Aug. 27 against San Diego.