Kaprielian (shoulder) was optioned to Triple-A Las Vegas on Saturday, Jane Lee of MLB.com reports.
Kaprielian won't open the season on the big-league roster, though that was true before this transaction. He's unlikely to open the year anywhere but the injured list, as he's yet to resume throwing after being shut down with a lat strain in mid-February. The Athletics will probably be happy for him to throw any innings at any level this season, something he hasn't done since 2016.