Both optioned players are eligible to return Tuesday, after the conclusion of Albuquerque's season. Both remained with the Major League club and worked out Sunday.
Frias, in fact, might start Wednesday's game against Washington.
The Dodgers also will promote a handful of players Monday. The most likely are outfielder Joc Pederson, catcher Tim Federowicz, infielders Erisbel Arruebarrena and Alex Guerrero and reliever Yimi Garcia.
The club also was in on talks for left-handed slugger Adam Dunn before he was dealt by the White Sox to Oakland.
One possible September callup who has been off the radar is left-handed reliever Onelki Garcia, who has been out all year after elbow and knee operations. He was to make his season debut for Class A Advanced Rancho Cucamonga on Sunday, and Don Mattingly said Garcia is further along in his recovery from injury than Paco Rodriguez, who has a Teres Major muscle strain.
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.