Brian Matusz

Orioles left-hander Brian Matusz pitches during the fourth inning at Ed Smith Stadium. (Tommy Gilligan / USA Today Sports / March 11, 2014)

SARASOTA, FLA. — When left-hander Brian Matusz arrived in the major leagues in 2009, his changeup was an essential part of his four-pitch arsenal.

But as Matusz struggled as a starter before finding a home in the Orioles bullpen last season, he said lost his feel for the pitch.

Even though Matusz served as the club's best left-handed reliever in 2013 — his first full season in the bullpen — the 27-year-old has made it clear that he wants to be a starter again.

This offseason, Matusz realized that rediscovering his changeup would be vital to reaching that goal because it would help him get right-handed hitters out, which has been his main obstacle to earning a regular spot in the rotation.

And this spring, Matusz confidently says the changeup has been his best pitch. He relied on a fastball-slider mix in the bullpen, but the 2008 first-round pick has regained his trust in the pitch as he continues to be stretched out as if preparing to be a starter.

"That's the key in terms of being a starter and getting right-handed hitters out," Matusz said of honing the changeup. "That's the difference, and fortunately, I've been able to work on that and make it better.

"It's been great. I feel like it's the changeup of the past. Being able to start this spring, and being able to stretch out and have the opportunity to throw it more, and be able to continue to work on it, and have swings and misses, and guys hitting it into the ground. That's clutch in terms of being a starter."

In his most recent start, Matusz went five scoreless innings and allowed just two hits in a Triple-A minor league game Tuesday after both split-squad games were rained out Monday. Including that outing, Matusz has allowed just two runs and six hits in 11 innings.

"The big thing has been being able to stretch out," Matusz said. "[On Tuesday], I threw the changeup a good portion of the game. I used it every inning. That's the key, at least for myself, and remembering from the past being a successful starter."

During Matusz's best major league season as a starter in 2010 — when he went 10-12 with a 4.30 ERA in 32 starts and finished the season with wins in seven of his final eight decisions — he threw his changeup 18.7 percent of the time, according to FanGraphs. That percentage has dropped every year since then, to just 10.3 percent last season.

"It's a very big weapon," Orioles catcher Matt Wieters said of Matusz's changeup. "He had a really good one, but he didn't have to use it much when he went to the bullpen. Whenever he starts, he is going to have to be able to use it."

Matusz said he has struggled with the pitch since the beginning of the 2011 season, when he missed the first two months of the season due to an intercostal strain. But now, Matusz said he's seeing a speed differential with the changeup of 10 to 12 mph from his low-90s fastball, and he's able to throw it from the same arm slot and arm speed.

"A couple years ago, with the injury, I never seemed to regain the feel for it," he said. "I'd either spike it on the ground or throw it high up in the zone. Now I'm able to just continuously work on it, and I've been able to throw it down in the zone and with good action.

"It's coming out with a good speed differential. Even the few times I've missed up in the zone with the changeup, guys have still swung threw it because of the speed differential from the look from the fastball."

With 10 days until Opening Day, Orioles manager Buck Showalter continues to extend Matusz's innings even though the five starting rotation spots appear to be set.

The club has its most quality pitching depth in years, and Matusz is the team's most tested left-handed reliever, especially with left-hander Troy Patton on the restricted list serving a 25-game suspension to open the season after testing positive for a banned substance.

"If nothing else, I think he's going to come out of here with a good feel for his changeup," Showalter said. "I don't know what the next 10 days are going to bring with transactions. I'm not going to say the word trade, injuries and what have you."

Matusz said: "For me, I've talked with Buck, and the impression I'm getting is that they're going to keep stretching me out. For me, I'll just continue to prepare and pitch and build up to be a starter. That's the game plan.

"We'll see how it all plays out over the next week and a half, but all of that is out of my control. For me, it's just about worrying about preparing and doing the things I can control and do. The main piece has been getting that changeup down."

In the bullpen last season, Matusz held left-handed hitters to a .168 batting average, but right-handers hit .302 against him. So even if he does return to the bullpen this season, regaining his changeup will help him in that role.

"So many times last year it would have helped us when we had left, right, left, and we could have left him in there to face a right-hander," Showalter said.

Matusz said his work with the changeup has also allowed him to refine his curveball. He said he has been working with new Orioles pitching coach Dave Wallace on throwing a curveball that has enough break that it literally lands on the plate.

"It's been a gradual progression of working with it, along with the curveball and slider," Matusz said. "There hasn't been just one thing where, 'Boom there it is.' But to be able to have four pitches, four options to go to, being a starter or going multiple innings, you have to have different looks. … In order to be a starter, the changeup is a must. Say one pitch isn't working on a given day. You have another pitch to balance it out.

Now confident throwing all four pitches this spring, Matusz finally feels like he's working with a full arsenal for the first time in several years. And he hopes that pays off in having the opportunity to be a starter.

"I'm getting the command back to where it needs to be," Matusz said. "I can throw [the changeup] for a strike — not just for a swing-and-miss pitch — but for a strike. It feels fantastic. I can't tell you how frustrating it's been the last few years not being able to throw the pitch that actually helped me get to where I am."

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