Erik Johnson possesses credentials worthy of a promotion to Triple-A Charlotte.

But Johnson, the White Sox's top pitching prospect currently with Double-A Birmingham, doesn't have to fulfill the prerequisite of pitching for the Knights before reaching his eventual destination with the Sox.

"He could continue his development at Birmingham," said assistant general manager Buddy Bell, who oversees the minor leagues. "We don't think it's imperative he goes to Charlotte before the big leagues.

"With hitters, we think it's important for them to go to Charlotte so they can adjust to soft and hard pitches."

Johnson, a second-round pick in 2011, is 7-2 with a 2.37 ERA in 13 starts for the Barons after throwing five no-hit innings Tuesday against Jacksonville.

The Sox were pleased that Johnson, 23, had to pitch without the command of his fastball he has shown for most of the first 21/2 months. He walked four but struck out five and was quick to praise his defense.

"When I needed it, I got it," Johnson said Wednesday in a telephone interview.

The Sox rotation has absorbed the losses of Gavin Floyd and Jake Peavy, along with missing John Danks for the first 71/2 weeks. The dependability of Dylan Axelrod and Hector Santiago has allowed the Sox to develop their starting pitching prospects naturally, but they have two doubleheaders scheduled because of rainouts as well as two more games to make up because of postponements.

That could pave the way for Johnson to receive a promotion, but he's downplaying that scenario.

"I'm just taking it day-by-day, pitch-by-pitch," said Johnson, who received a long look in spring training and pitched four innings without allowing an earned run against the Royals on March 24.