JUPITER, Fla. -- The final month of the season will be like starting over for Marlins right-hander Jarred Cosart. If Saturday is a preview of what's to come, the 25-year-old should be as good as new when he rejoins the big league club.

On the Minor League disabled list with vertigo, Cosart threw four shutout innings over 44 pitches in the Gulf Coast League Marlins' 8-2 win over the Cardinals' affiliate at the Roger Dean Stadium complex.

"I feel amazing," Cosart said. "No dizziness. No vertigo. It's huge. It's a blessing."

It's another step forward in what has been a rough and frustrating season for Cosart, who's gone 1-4 with a 5.36 ERA in 45 1/3 innings for Miami. On May 17, he was placed on the DL with vertigo.

The Marlins optioned Cosart to Triple-A New Orleans on July 4 after he allowed seven runs in 1 2/3 innings in a loss to the Cubs at Wrigley Field.

At New Orleans, Cosart had a relapse with his vertigo during a July 17 start.

A few weeks ago, the right-hander saw a specialist in Chicago, and he was diagnosed with an inner left ear disorder. The condition affected his balance and gravity, and the doctors said he may have been dealing with the condition all season.

Cosart promises to be a big part of the rotation in 2016, and he is aiming to regain his old form in September.

"I feel great," he said. "I'm a little out of shape right now. Obviously, I had to take 2 1/2, three weeks off of all activity. I didn't have any signs or dizziness today or the vertigo today, or for the past couple of weeks."

Cosart's velocity was at 94 mph on Saturday, and he scattered two hits, struck out two and walked one. He had a wild pitch in the first inning, but overall was able to command his pitches to both sides of the plate.

Cosart induced seven groundouts and two flyouts.

Before rejoining the Marlins, he is expected to make two rehab-assignment starts, with the first likely with Class A Advanced Jupiter.

"Obviously it's been a rough year for the Miami organization, in general, with high expectations, we didn't succeed, with myself as a big part of that, missing two months," Cosart said. "Hopefully I get back and show Miami what I did last year again in September and carry it over into 2016."

Acquired from the Astros in July 2014, Cosart was 13-11 with a 3.69 ERA in 180 1/3 innings last year, going 4-4 with a 2.39 ERA after being traded to the Marlins.

"Now, it's just getting my legs back up underneath me and getting back to who I am," he said. "Hopefully I can get back to Miami soon and help them get to higher places in 2016."