Guerra saved 21 games for the Dodgers in 2011 and eight in 2012, but the right-hander spent much of last season at Triple-A Albuquerque after a rough month of May. The Dodgers have 10 days to trade or release Guerra or outright him to the Minor Leagues if he clears waivers.
"Just kind of came down to numbers, really, and spots," Dodgers manager Don Mattingly said of Guerra. "He's kind of been back and forth the last couple of years. Obviously Javy's a guy that I like. ... I think Javy being out of options and getting designated, I feel like it speaks kind of to our [bullpen] depth."
As expected, outfielders Matt Kemp and Carl Crawford won't be making the trip.
Kemp will remain at Camelback Ranch to continue his work as he comes back from ankle surgery. Crawford is an expectant father and will be placed on paternity leave.
The Dodgers have starting pitchers Clayton Kershaw and Sunday's starter, Hyun-Jin Ryu, on the roster for the two games against the D-backs. Starter Paul Maholm also is headed to Australia.
"We have a long journey ahead of us," Ryu said with a wry smile, adding that he'll sleep a lot on the airplane.
Infielders Adrian Gonzalez, Dee Gordon, Hanley Ramirez and Juan Uribe all started Sunday and are making the trip. So are Alex Guerrero and Miguel Rojas.
The outfielders are Andre Ethier, Yasiel Puig, Scott Van Slyke, Mike Baxter and Joc Pederson. Ethier and Puig started Sunday.
Catchers A.J. Ellis, Tim Federowicz and Drew Butera are among the group. For the bullpen, closer Kenley Jansen, Brian Wilson, Chris Perez, J.P. Howell, Paco Rodriguez, Jamey Wright, Seth Rosin, Jose Dominguez, Zach Lee, Red Patterson and Chris Withrow are off to Australia.
Ellis was asked if he's ready for the trip.
"Don't have a choice," he said. "I am excited about it. It's going to be a great trip. Glad we have a chance to get acclimated, get our legs under us and play that exhibition game. It's nice to have that on the schedule, too."
Either Lee or Patterson will start the exhibition game against the Australian national team on Thursday.
Perez pitched two-thirds of an inning Sunday and struck out one with a walk. Jansen struck out one in his lone inning.
Starting pitchers Zack Greinke, Josh Beckett and Dan Haren will remain in Arizona. Beckett is a candidate for the disabled list while Greinke and Haren will continue to get their work in Minor League games.
The Dodgers must select their 25-man active roster by Friday, before the first game in Sydney.
Catcher Miguel Olivo was reassigned to Minor League camp and left-hander Onelki Garcia was placed on the 60-day disabled list after left elbow surgery.
Of the 30 going to Australia, six were non-roster invitees to Spring Training -- Figgins, Rojas, Turner, Pederson, Lee and Patterson.