JUPITER, Fla. -- The Tigers announced Friday that top pitching prospect Michael Fulmer has been optioned to Triple-A Toledo.

Fulmer, who was acquired by Detroit in the Yoenis Cespedes trade with the Mets last July, had a 6.14 ERA in 7 1/3 innings pitched this spring, and there had been some debate whether to stretch him out to be a starter or move him to the bullpen. He is the Tigers' No. 1 prospect according to MLBPipeline.com.

"I think ultimately the development will serve him better than forcing him to pitch at the Major League level when he's probably not quite ready," Tigers manager Brad Ausmus said prior to Friday's 2-0 win over the Cardinals at Roger Dean Stadium. "And it allows him to start and work on that changeup, which I think is going to be important for him long-term. If he's pitching at the big league level, you can't be working on a third pitch coming out of the bullpen."

Fulmer posted a 6-2 record and a 1.88 ERA with Double-A Binghamton last summer before the trade and a 4-1 record with a 2.84 ERA in six starts with Double-A Erie after the deal. Fulmer has a career record of 26-24 with a 3.17 ERA in 76 games in the Minor Leagues.

The moves comes about a week after Tigers GM Al Avila told reporters that it was in Fulmer's "best interest" to be a starter "because the development process is better."

Ausmus is confident that the 23-year-old Fulmer, who was a first-round pick by the Mets in 2011, will eventually be on the Tigers' Major League roster, possibly later in 2016.

"I don't have that good of a crystal ball, but it wouldn't surprise me if it was sometime this year," Ausmus said. "Young kid with potential, good makeup, good build. Did everything we asked. I think he'll be a big league pitcher at some point."

Steve Dorsey is a contributor to MLB.com.