When Matt Boyd needed to go on the 15-day injured list with a left biceps strain, it was just a day after the Cubs had lost Cade Horton to what would eventually be a season-ending elbow injury. Things looked dire on the pitching front.

And yet, Cubs starting pitchers held their own, posting a collective ERA of 3.54 between April 6 and the 21st, the day before Boyd returned from the injured list. They are a big part of the reason why the Cubs have gone from two games below .500 the day Boyd went down to riding an eight-game winning streak that’s brought them to six games above .500. Boyd tossed 4 2/3 innings of two-run ball in Wednesday’s 7-2 win over the Phillies.

“It’s been the key to this run we’ve had,” Craig Counsell said of his rotation. “The length [of starts], the quality, those are really meaningful.”

Having Boyd back is big for the rotation, and if not for the depth in the pitching staff, Counsell and the Cubs training staff might have felt a little less comfortable putting him on the injured list two weeks ago. Counsell said that Boyd started feeling mostly healthy as many as 12 days ago, but the decision to place Boyd on the IL was one they felt good about for the sake of Boyd’s long-term health and because of the arms ready to step up in his absence.

Namely, Colin Rea and Javier Assad. Rea has been tasked more or less with taking Horton’s spot in the rotation, and Assad was called up from Triple-A Iowa to do the same for Boyd. In his last three outings, Rea has thrown a quality start in two of them. Assad came up from Des Moines and pitched 5 2/3 scoreless innings against the Rays the day after Boyd went on the IL. Over the weekend, Assad helped finish off the sweep against the Mets with 5 2/3 innings of one-run ball.

“What they did isn’t easy,” Boyd said. “Just getting the ball flipped to you and say, ‘Hey, you’re starting tomorrow or the next day. You have to hop on a plane and come do that, in [Assad’s] case. And [Rea], he’s getting ready every day and then he’s told, ‘Hey, okay, now you’re going to start this game.

“It’s a hard thing to do, and it takes a ton of maturity. It takes understanding what you expect of yourself when the ball’s in your hand, and both those guys did that.”

Because of their understated personalities, it might be easy for fans to overlook or even take for granted the yeoman’s work Rea and Assad have done. Neither pitcher is going to attract a lot of attention, but both will take the ball whenever and however called upon and get the job done.

Doing that put them both on hitters’ radars years ago, and Rea and Assad have earned the respect of opposing batters. Enough so that when Rea joined the Cubs, it was cause for relief among them.

“Since the day that [Rea] got signed over here, I was probably the happiest man,” Michael Busch said. “Facing him in Milwaukee in 2024, it was a tough at-bat. Five pitches, really good stuff, command, everything. So when he became a Cubbie I had a little of my own celebration.”

The other side of the Cubs’ eight-game winning streak is an offense that has picked up considerably from the first couple of weeks. Busch is one of a few guys who got off to slow starts, but he, like the others, is showing signs of heating up. Busch homered in Wednesday’s win, and he’s boosted his batting average by 70 points in the last 11 days.

With him, Pete Crow-Armstrong is also coming to life at the plate. He had three hits on Wednesday, including a second-inning RBI double. Crow-Armstrong is hitting .320 in his last seven games, some of which he credits to having Seiya Suzuki back from his early season stint on the injured list.

“Adding Seiya back in the lineup adds a lot of ease to how I approach an at-bat,” Crow-Armstrong said.

That ease has helped Crow-Armstrong take some of the effort out of his swings, which in turn helps with his timing, Crow-Armstrong said. That’s a big part of why he is trending in the right direction.

Those are the kinds of things that come together to put a team on an eight-game winning streak. The Cubs are consistently reliable when it comes to stuff like defense and baserunning, and as the pitching staff gets healthy and the offense comes fully to life, they make their way toward the top of the division.

When the Cubs lost the second game of their weekend series against the Pirates on April 11, both Counsell and Bregman were confident that things would turn for the positive.

“It’ll turn […] We’re all every single day getting after it, trying to turn it. And I feel like over the course of 162 the cream will rise to the top, and we’ll play good baseball,” Bregman said then.

Since that game, the Cubs have gone 9-1. It’s probably safe to say they were right. And going forward, things like getting Boyd back in the rotation will help the Cubs keep moving in this direction. The National League Central is shaping up to be a very tough division, but the Cubs have the the best run differential by 17 runs and only the Pirates have a lower team ERA.

“It speaks to the professional approach that we have,” Boyd said of the team’s success of late. “The experience of the guys in that clubhouse; it’s in those moments of those kind of valleys […] whether it’s a losing streak or a tough streak at the plate or a tough streak on the mound, the experience of that you lean on and say, ‘Stay the course, make some small adjustments. Keep defining success in the right way.

“The experience of those guys is what buoys that in those tough times.”