Cabrera was hitting .283 with a career-high 108 hits in 95 games while leading the National League in steals with 37. The 26-year old ranks fourth among all Major League shortstops in WAR (3.0), so replacing him will be no easy task.
"I think they can handle it," manager Bud Black said. "It's a great opportunity for Logan and the steadiness of Ronny will help."
Forsythe has played six games at shortstop in his career. He's spent time this season at second base, third base and the outfield, and is hitting .209 with four homers and 13 RBIs.
"I'm excited for Logan," Padres third baseman Chase Headley said. "It's an opportunity he's deserved for a long time. ... I like the way he prepares himself and the way he works."
Cedeno was signed as insurance, as he's played parts of nine seasons mostly at shortstop. He spent 51 games with the Astros this season, and hit .220 with six doubles and 12 runs scored, but was designated for assignment on July 22. In two games for Class A Lake Elsinore, he was 1-for-8 with a double, a run scored and two walks.
Cabrera was placed on the restricted list with the suspension, so selecting Cedeno gives the club a full 40-man roster.
Jamal Collier is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.