The recommendation from Miller and Lilliquist came after they watched Rosenthal fit in as a member of big league camp for several weeks. Rosenthal, whom MLB.com ranks as the organization's fourth-best pitching prospect, made five Grapefruit League appearances before being reassigned to Minor League camp.
He allowed one earned run and five hits in seven innings. The team's radar gun clocked Rosenthal's fastball constantly in the 94-96 mph range.
In making this move to Double-A, Rosenthal will be challenged to utilize his secondary pitches and keep his fastball down in the zone. Both have been strengths during Rosenthal's climb in the Minors, which began after he was a 21st-round pick in the 2009 First-Year Player Draft.
"The feeling is that he should be able to handle that level," Vuch said. "In terms of pure stuff, he's got easily Double-A and above stuff. It's really more about location."
Rosenthal made 22 low Class A starts in 2011, finishing 7-7 with a 4.11 EREA. He was a Midwest League All-Star and ranked fourth among all Cardinals Minor Leaguers with 133 strikeouts. Those came in 120 1/3 innings.
Rosenthal won't be the only highly-touted prospect making the leap from low Class A to Double-A leap. So, too, will 19-year-old outfielder Oscar Taveras, who batted a league-best .386 with 40 extra-base hits and 62 RBIs last year. The Cardinals' decision to have Taveras skip high Class A was prompted by the continued maturation he showed this spring.
"We brought him in the first day of early camp and sat him down and explained that your bat is every bit of Double-A level but the rest of your game is not," Vuch said of Taveras, whom MLB.com ranks as the Cardinals' top position player prospect. "We told him that he has the next four or five weeks to show us where he belongs. He really took the conversation to heart, really applied himself during batting practice and really went at it with good energy."
Vuch was quick to distinguish Taveras' need to mature from laziness, noting that past lapses in hustle or focus have typically sprouted from Taveras' personal frustration. Those weren't issues he had this spring.
Taveras also showed in the Arizona Fall League that he can handle himself against more advanced Minor League pitching. Though he was the second-youngest Fall League participant last year, Taveras hit .307 in 19 games. Having proved that his bat was Double-A ready, Taveras stepped up his defense and improved his baserunning during Spring Training.
He was even exposed to Major League pitching, making seven game appearances in Grapefruit League games as a guest Minor League call-up. He went 2-for-8 at the plate.
Taveras and Rosenthal may highlight Springfield's 2012 roster, but they are hardly the only top prospects on it. Four of MLB.com's top nine prospects will begin the season in Springfield. That includes infielder and former first-round Draft pick Kolten Wong and left-hander John Gast.