The left-hander tossed four no-hit innings, striking out four while allowing two walks in Class A Quad Cities' 7-6 loss to Kane County on Wednesday.
Calhoun walked the second batter he faced, Tyreace House, but helped pick him off soon after. He also issued a base on balls to Anthony Aliotti in the second, but got out of the inning without further trouble.
He struck out the side -- Juan Nunez, Michael Gilmartin and Conner Crumbliss -- in the third.
Leonardo Gil reached on a fielding error by shortstop Ryan Jackson in the fourth, but Calhoun fanned Aliotti to end his outing.
Calhoun, who sports a 3.45 ERA, doesn't have a decision this season. He gave up four earned runs on nine hits with five strikeouts over 4 2/3 innings in his longest start April 17 against Wisconsin.
The 23-year-old Murray State product was selected by the Cardinals in the 29th round of the 2009 Draft. He went 2-0 with a 1.86 ERA over 48 1/3 innings in 12 games, including six starts, for Class A Short-Season Batavia last year. In his Muckdogs debut June 21, he threw three no-hit frames in a 5-1 victory over Auburn.