Forsythe has been on the disabled list since March 31 with plantar fasciitis in his right foot. He is expected to see playing time at second base, shortstop and third base during his rehab stint.
Outfielder Cameron Maybin also is making strides during a rehab assignment in Tucson.
He had five hits in his first 11 at-bats, showing improvement from his .091 average in 33 at-bats with the Padres in April.
"He's making good strides, getting his legs underneath him," Padres manager Bud Black said. "He's working his way back to feeling confident about his wrist and getting some hits to feel confident about when he steps into the box."
Maybin has been on the disabled list since April 17 with right wrist impingement. Black has said he would like to see Maybin get around 30 at-bats in Tucson.
Jamal Collier is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.