The right-handed-hitting first baseman/outfielder will join Oakland in Cleveland on Friday, and he is expected to start against most lefties, with left-handed-hitting Moss remaining in a platoon role despite his success against pitchers of either dexterity this year.
Moss is 8-for-25 (.320) against southpaws and 30-for-111 (.270) when facing right-handed pitchers.
Barton, however, was hitting just .158 overall with no home runs through 30 games in his eighth season with the organization.
The A's have 10 days to trade, release or pass Barton through waivers. He's been designated by them twice before, choosing a Minor League assignment over free agency on each occasion.
Blanks was 2-for-10 in his brief stint with San Diego this year, before being optioned back to Triple-A El Paso this week to make room for Carlos Quentin. He hit .265 with nine homers and 20 RBIs in 27 games with the Chihuahuas this season.
The 6-foot-6 Blanks, a 42nd-round pick by the Padres in 2004, made his big league debut against the A's on June 19, 2009, collecting his first hit the following day.
A natural first baseman, Blanks was asked to play the corner-outfield spots in San Diego, turning him into the type of versatile piece the A's have made a habit of collecting in recent years.
Blanks played in a career-high 88 games in 2013, hitting .243 with eight home runs and 35 RBIs in 308 plate appearances -- including a .282 mark against lefties -- following a handful of injury-ridden years.
The 27-year-old had Tommy John surgery on his right elbow in 2010, as well as season-ending surgery on his left shoulder in April 2012. Blanks also had issues with a strained arch in his right foot and, last season, left Achilles tendinitis.
Blanks has options left, giving Oakland some flexibility with him. The club still has another right-handed-hitting first baseman in Nate Freiman waiting in the wings at Triple-A Sacramento.
That's where Goebbert was hitting .257 with six homers and 25 RBIs in 31 games for the River Cats.
Jane Lee is a reporter for MLB.com. Read her blog, Major Lee-ague, and follow her on Twitter @JaneMLB. Corey Brock contributed to this report. This story was not subject to the approval of Major League Baseball or its clubs.