Cubs to test new rule for doubleheader

A new roster rule that took effect this year allows teams to add a 26th player on days they’re forced into doubleheaders – as the Cubs are Saturday at Cincinnati.

It gives them an opportunity to bring up a starting pitcher for one of the games. But the likeliest candidate, Casey Coleman, left Saturday’s start at AAA with shoulder soreness, and his status may not be known for at least a few days.

Next-in-line candidate, Chris Rusin, isn’t on the 40-man roster. And neither is Ryan Rowland-Smith, who’s pitched well since joining the Iowa rotation with Brooks Raley’s promotion, and whose regular day would fall on Saturday. Either could be added by shifting a DL guy to the 60-day.

The Cubs could add a bullpen guy and use Thursday’s off day to double up Raley and Jeff Samardzija Saturday – delaying the issue for three days.