The Chicago White Sox had lost no more than three straight games before clinching the franchise's first playoff berth since 2008 on Sept. 17.
Chicago has dropped seven of eight since, including six in a row entering Saturday's visit from the Chicago Cubs.
"The beautiful thing is that we are in the playoffs," White Sox reliever Aaron Bummer said. "This isn't a team that likes to dwell on things. We're a big believer in it's a new day, and each day, each day is a gift. We're going to move forward with that. It has been a tough stretch, but this doesn't mean anything in the postseason."
Still, the White Sox (34-24) would prefer to arrive in the American League postseason with at least a modicum of momentum. After residing in first place in the AL Central for much of the stretch run, the White Sox now find themselves in a second-place tie with the Cleveland Indians, one game behind the Minnesota Twins.
"It's not like we don't know we are a good team. We just have to put it together," White Sox right-hander Dylan Cease said. "We've had a good season. The last week has been good. We have good players. We don't need to panic or do anything drastically different. We just have to bring it to the park."
Fueled by a five-home run barrage and Yu Darvish's seven shutout innings, the Cubs rolled to a 10-0 victory in Friday's series opener. The Cubs (33-25) snapped a three-game losing streak while lowering their magic number to clinch the National League Central title to one.
Breaking out against the White Sox was especially encouraging on the heels of an offensive slump.
"We're already in the postseason, so let's work on having good at-bats, work on finding a different feeling ... so when the time comes, you're not just trying to flip the switch and hope that you can roll it out there and be a new lineup," Cubs second baseman Jason Kipnis said.
Cubs left-hander Jon Lester (3-2, 4.40 ERA) will look to win consecutive starts for the first time in 2020 in his final regular-season start. Lester pitched six shutout innings Monday to defeat the Pittsburgh Pirates. He is 11-7 with a 4.48 ERA in 20 career starts against the White Sox with 111 strikeouts in 124 2/3 innings.
Lester surrendered eight runs on nine hits -- including four homers -- in 3 2/3 innings in a 10-1 road loss to the White Sox on Aug. 21.
Rookie right-hander Dane Dunning (2-0, 3.19 ERA) gets the call for the White Sox in his seventh career start. Dunning worked a career-low four innings Monday in a no-decision at Cleveland, scattering four runs and six hits with one walk and five strikeouts.
Cubs third baseman Kris Bryant remained out Friday with right oblique tightness while White Sox left fielder Eloy Jimenez is not expected to play in the series with a mid-foot sprain he suffered in Thursday's loss at Cleveland.
The Cubs are 2-2 against the White Sox this season. The White Sox lead the all-time series 64-62, including a 32-30 edge at Guaranteed Rate Field.
--Field Level Media
|Chi. White Sox||34-24||L6||17-11||17-13||0-0||25-15||0-0||9-9|
|Chi. Cubs||Chi. White Sox|
|9/25/20||CHC 10||CHW 0||.278||5||1.103||.100||0||.262|