PHOENIX -- The D-backs optioned pitcher Enrique Gonzalez to Triple-A Tucson after Wednesday's game, with a corresponding move involving a pitcher coming before Friday's game, said manager Bob Melvin.

Gonzalez allowed three runs on four hits in two innings in Monday's 10-2 loss, his only appearance since being called up from Triple-A for the first time this season before Saturday's game, when Randy Johnson was placed on the disabled list.

Melvin said the team is discussing making Gonzalez the Triple-A pitcher to throw on the same days that Johnson does, so he would be ready for a spot start in case Johnson's back flares up days before a start. If Johnson misses his next start on Tuesday against the Dodgers, when he can return from the DL, Edgar Gonzalez would "probably" get the call, but the team is still deciding on what to do thereafter.