This story was excerpted from Jake Rill’s Orioles Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

BALTIMORE -- Grayson Rodriguez never shies away from pitching against tough competition. That’s a good thing, too, because the 23-year-old rookie right-hander has faced some of the best MLB has to offer since rejoining the Orioles’ rotation last month.

Here’s who Rodriguez has started against since getting called up from Triple-A Norfolk:

July 17: The Dodgers, who lead the National League West.
July 22: The Rays, who sit in first in the American League Wild Card standings.
July 28: The Yankees, an AL Wild Card contender.
Aug. 2: The Blue Jays, who sit in third in the AL Wild Card standings.
Tuesday: The Astros, who sit in second in the AL Wild Card standings.

The results for Rodriguez? A 3.45 ERA (11 earned runs allowed in 28 2/3 innings) with 24 strikeouts. He recorded his first big league quality start vs. New York (6 1/3 scoreless innings) and notched another vs. Houston (two runs allowed in six innings).

The main reason for the results? His budding confidence.

“Every start that he makes that he has success, I think the confidence is going to continue to grow,” manager Brandon Hyde said. “I feel like I’ve seen that, honestly, since he’s been back. It’s the tempo in his delivery, how he’s walking around the mound, the stuff. The command has been a huge improvement. The slider’s gotten better. Carrying his velocity deep into the game.”

The stuff was never the issue. Rodriguez always had an overpowering four-seam fastball and nasty breaking pitches capable of getting Major League hitters to swing and miss. He mostly struggled to locate those offerings, resulting in too many free passes and mistake pitches -- he issued 21 walks and gave up 13 home runs in 45 1/3 innings over his 10-start stint with the O’s from April 5-May 26.

Rodriguez has worked on retooling his arsenal, though, to put himself in a better position to have success at the big league level. These are the most notable changes:

• He’s thrown his fastball at least 46.2% of the time in each of his first five starts back. He reached that percentage in only four of his first 10 MLB outings. The heater is also coming out of his hand much harder -- the 36 fastest pitches of his big league career have all been thrown over his past five starts.

• His slider usage is on the rise. He threw it a career-high 34.4% on Tuesday (32 of his 93 pitches) after not throwing it more than 15.6% of the time since May 20 against Toronto. The Astros swung at 18 sliders and whiffed on seven of them. It helps that this pitch has also had an uptick in velocity from April (average of 81 mph) and May (80.9) to July (83.6) and August (83.5).

“The slider has been a lot better since I’ve been back in the big leagues,” Rodriguez said. “That was something that I didn’t really have before.”

• While he continues to throw sporadic changeups and curveballs, the cutter has nearly been removed from his repertoire entirely. He’s thrown only nine in five starts after throwing 109 over his first 10 big league outings.

Rodriguez has repeatedly praised members of the Orioles’ staff -- pitching coach/director of pitching Chris Holt, assistant pitching coach Darren Holmes and Triple-A pitching coach Justin Ramsey -- for helping to refine his pitches and determining the right mix.

There’s clear progress that’s been made over his past five outings: Rodriguez is getting deeper into games (at least five innings each time out); he hasn’t issued more than two walks in a start; and he hasn’t given up a home run since returning.

“A lot better than the first set,” Rodriguez said of his improvement. “Just being able to go out and go six innings, keep them to two runs, that’s huge from my standpoint.”

That’s also exactly the type of outing the Orioles are hoping to get from Rodriguez at this stage in his career. But the former top prospect has an even higher ceiling, which he’s moved much closer to following his early struggles.

“You saw a young starting pitcher that had to deal with a little bit of adversity, and that’s not a terrible thing. And I said that at the time -- this is not abnormal for this to happen,” Hyde said. “We get wrapped up with young players coming up here and having a bunch of immediate success, and that’s not always the case, even really, really talented ones like Grayson.”