Arias is batting .255 in 14 games this season, but his biggest contributions to the club have been in the field.
On Saturday with the tying run at the plate for the D-backs, Arias made a backhanded snag down the left-field line to steal an extra-base hit away from Ryan Roberts.
"With the job he's done, he's handled the bat and played good third base, he's been the silver lining through the Pablo injury," Bochy said. "He's picked us up."
Utility player Emmanuel Burris will be the likely backup at third for Arias.
"He's still going to be in the mix," Bochy said of Burriss. "Right-handed at-bats haven't been as well as he would like or I would like, but he'll keep working."