CINCINNATI -- In his first start for the Cubs, Justin Steele's slider abandoned him against the Brewers, and the rookie lefty had to lean on the remainder of his repertoire.

The pitch returned Monday, and Steele flashed a more overpowering version of himself in a four-inning outing against the Reds.

"It felt good to have the slider a little bit more," Steele said. "I was able to utilize it a lot more -- got some more swings and misses with it. Yeah, it felt good to get out there and have that weapon."

With the slider fully operational, Steele was able to feature a strong five-pitch mix against Cincinnati. After going heavier with the sinker and changeup against Milwaukee on Aug. 10, Steele was able to lean more on a four-seam and slider-led arsenal in Monday's game.

Overall, Steele ended with 13 whiffs out of 38 swings (34 percent) against the Reds, compared to just four whiffs on 29 swings (14 percent) in the previous start. Cincinnati had four swinging strikes against the slider alone, and another five against a four-seamer that averaged 94.4 mph and topped out at 96.6 mph, per Statcast.

"He had electric stuff," Cubs manager David Ross said. "Good pitch mix. It looked like the slider -- the breaking stuff -- was really sharp. I was pretty impressed."

Winkler designated for assignment

Right-hander Dan Winkler was one of Ross' trusted veteran arms throughout last season and was so again for the first half this year. Winkler's recent struggles, however, became too much for the Cubs to take on.

Chicago designated Winkler for assignment prior to Tuesday's game against the Reds. The righty was charged with four runs in Monday's 14-5 loss, giving him 13 runs allowed in his past three outings (1 2/3 innings).

"That's a tough conversation," Ross said. "Ever since I've been the manager, he's given me a lot, worked through a lot, some ups and downs. I think we're at a spot to maybe give somebody else a shot in a moment where he's just struggling a little bit.

"And I don't think we have a lot of time to help him work through those moments right now."

Worth noting

• For Wednesday's game against the Reds, Ross said the Cubs are planning on calling righty Adrian Sampson up from Triple-A Iowa to make a spot start. Sampson, 29, has big league experience with the Mariners (2016 and Rangers ('18-19), and he has a 4.96 ERA in 16 games for Iowa this year.

"He throws strikes," Ross said. "He's stretched out -- 100-plus pitches. He can give us some length out of the starter role. There was a couple options, but ultimately, we settled on him."

• Ross penciled both catcher Austin Romine (batting seventh) and shortstop Andrew Romine (batting eighth) into Tuesday's starting lineup. It marked the first time brothers started in the same game for the Cubs franchise since Kid and Lew Camp did so on May 8, 1894, per team historian Ed Hartig.

• Ross said he is considering pairing outfielders Rafael Ortega (against righties) and Michael Hermosillo (against lefties) as a platoon in center field. Hermosillo had his contract selected by the Cubs on Tuesday after hitting .310 with 10 homers and a 1.048 OPS in 42 games this season at Triple-A.

Quotable

"The toughest part for me was I didn't know who to hit in front of who with the two down there in the bottom. I didn't know if that was going to start an argument or a conversation in my office, like, 'Why is he hitting in front of me?' I tried to do all my homework on that." -- Ross, joking about having the Romine brothers in the lineup