"I don't see it happening," Roberts said Monday, ahead of a four-game series on the road against the Miami Marlins.
Bauer is facing allegations of sexual assault, and he was placed on leave by MLB on Friday, which forced him to miss his scheduled start against the Washington Nationals on the Fourth of July.
Bauer, whose side has denied the allegations, declined to appeal MLB's decision.
Administrative leave, adopted under a joint domestic violence policy between MLB and the MLB Players Association, is not considered a suspension; the player still gets his full salary despite not residing on the active roster.
MLB can request an extension of seven additional days with consent from the MLBPA. Doing so would keep Bauer off the field through the All-Star break, buying more time for an ongoing investigation.
Bauer has been accused by a woman of choking her until she lost consciousness on multiple occasions, punching her in several areas of her body and leaving her with injuries that required hospitalization over the course of two sexual encounters earlier this year, according to a domestic violence restraining order that was filed in L.A. County Superior Court last week, copies of which were obtained by ESPN on Wednesday.
Bauer also is under criminal investigation by the Pasadena police department. The case is expected to be sent to the Pasadena District Attorney's Office.
There have been repeated instances in the past that MLB players under criminal investigation have shifted to indefinite leave, to allow time for resolution of the legal matters and for baseball to advance its own inquiries.