PITTSBURGH -- As the Cubs have navigated through an assortment of rotation complications this season, lefty Justin Steele has been a steadying hand. Now, as the North Siders keep pushing for a place on the October stage, the predictability of Steele carries even greater import.

“He's been a metronome for us,” Cubs president of baseball operations Jed Hoyer said on Thursday.

That description held true at PNC Park, where Steele once again notched a quality start to help put the Cubs on a course for a 5-4, 10-inning victory over the Pirates. The left-hander shook off some early setbacks, then settled in and continued his National League Cy Young Award campaign.

When Steele headed off the hill with the game deadlocked, turning things over to Chicago’s relief corps after six frames, he did so with his 17th quality start in tow. Only Gerritt Cole and Logan Webb have more this year, with 18 apiece. Steele’s 2.80 ERA is second only to Blake Snell in all of baseball.

“I put a ton of work in the offseason to get to this point,” Steele said. “I want to be the guy that we can rely on, that goes out there and gives us good start after good start. I want to be consistent. That's what makes a really good starting pitcher.”

With the NL Central-leading Brewers idle on Thursday, the win pulled the Cubs within three games of first place in the division. The North Siders also maintained their grip on the second NL Wild Card spot, moving within two games of the Phillies for the top slot.

Steele has been a key piece to Chicago’s ascension to contention, and that will continue to be the case over the next six weeks. As Cubs manager David Ross summed things up recently: “If we're going to make the playoffs, he's going to be a big part of that.”

The Cubs lack All-Star Marcus Stroman for an unknown amount of time as he rests his fractured rib cage cartilage at home in Tampa, Fla. Lefty Drew Smyly, who recently returned to the rotation, is expected to move back to the bullpen after another tough start, per Hoyer.

After a rough start to the season, Jameson Taillon has been much more consistent over the past six weeks. Kyle Hendricks, who was sidelined until late May due to an arm issue, has been reliable since returning. Javier Assad has been on a nice run of late while starting as well.

For the fifth spot in Stroman’s absence, the Cubs are currently weighing their options. The top in-house solution would be righty Hayden Wesneski, who currently resides in the bullpen as a multi-inning option. Down on the farm, lefty Jordan Wicks, MLB Pipeline’s No. 10 Cubs prospect, is off the 40-man roster but very much on the radar.

All of this makes Steele’s punch-in mentality crucial, even as he starts collecting career highs in innings and starts.

“He's ready. He wants it,” Cubs pitching coach Tommy Hottovy said. “He wants to prove he can do it over a long season and continue to carry the workload.”

Steele missed a short stretch in June due to a minor arm issue, but he sits at 138 innings. That tops the career-high 119 frames he logged in 2022 for the Cubs. Prior to that, the lefty’s highest innings total was 98 2/3 in ‘17, when he was on a strong run at High-A until Tommy John surgery.

Hottovy said the Cubs’ staff has closely monitored all the metrics surrounding Steele this season, and the pitch shapes and data have stayed in the expected ranges. After a brief dip in velocity, Steele has been on the upswing again, including in Thursday's outing against Pittsburgh.

“The best thing that I think I can say about Steeley right now,” said Hottovy, “is this is the best I've seen him in terms of physicality, his shape, the work he puts in, his routine. He's locked in.”

Against the Pirates, Steele also showed off his resiliency.

Steele allowed an unearned run -- paved by his own fielding error -- in the second and then gave up a towering, two-run blast to Joshua Palacios in the third. The baseball soared into the Allegheny River beyond the right-field wall, but Steele shook it off and kept the Pirates off the board from there.

“I feel like at times,” Cubs shortstop Dansby Swanson said, “when his back's against the wall, like, you can just see him continue to compete and just make it happen. I think that that's such an underrated trait of his.”

That, along with the predictability.

“He locked it down,” Ross said. “Nice, nice job. That's what we're expecting him to do. He's at that level now. He's our horse. We're going to lean on him.”