JUPITER, Fla. -- The mechanical adjustments are clicking for Jarred Cosart, and the Marlins right-hander is seeing the results. The 25-year-old threw three shutout innings of relief on Wednesday in a 4-2 loss to the Nationals at Roger Dean Stadium.
Competing for a rotation spot, Cosart now has thrown six innings without allowing a run in three Grapefruit League games.
In relief of Wei-Yin Chen, who worked four innings, Cosart pounded the strike zone, throwing 40 pitches, of which 26 went for strikes. He added a strikeout, giving him five in six spring innings.
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"Obviously, he's on the attack, which is what I liked," manager Don Mattingly said. "Aggressive all day, it seemed like. There was nothing not to like."
About the only bump in the road for Cosart this Spring Training came in his first outing on March 4, when he threw one inning against the Nationals but bruised his right knee on a collision while covering third base.

Since then, he's been working back and getting his pitch count up. After his appearance against the Nationals, he threw 20 more pitches in the bullpen, ramping him up to 65 on the day.
"That's the thing right now, just building him," Mattingly said. "We've had a lot of guys we've wanted to get innings. He was part of that crew. That little hiccup that he had the first day kind of kicked him back two extra days. Other than that, he's good."
Next up for Cosart is a probable start on Monday against the Mets in Port St. Lucie, Fla. Chen is also scheduled to throw that day, but the lefty is expected to pitch in a Minor League game on a backfield.
Cosart's velocity was 94-96 mph, plus he's mixing in more changeups and breaking pitches.
"Pretty much everything was working," the right-hander said. "That was the first time I really busted out the changeup. I think I threw four, and three of them were quality."
If there is an area he is looking to improve it's his strikeout totals. He had six hitters in 0-2 counts on Wednesday, and fanned one.
"The ball is down," he said. "It's coming out good. The curveball is good, the changeup is good. The mechanical adjustments are really paying off. It's trying to go out there and compete every inning."