CHICAGO (AP) The Chicago Cubs have optioned right-hander Adam Warren to Triple-A Iowa to prepare him for a major league start.

The Cubs also placed lefty Clayton Richard on the 15-day disabled list because of a blister on his left middle finger, selected left-hander Gerardo Concepcion's contract and recalled righty Spencer Patton from Iowa before Tuesday's game against St. Louis.

Warren is 3-1 with a 4.56 ERA in 25 games. He made 17 starts and 43 appearances for the New York Yankees last season.

More from FoxSports

The Cubs plan to have him start two minor-league games and make one for them before the All-Star break. Warren might make another start after that.

Chicago will have played 24 consecutive days before the break. Stretching Warren will give the starters an extra day of rest.