According to multiple sources the Oakland Athletics have designated Rich Thompson for assignment, making room on the 40-man roster for callup Jim Miller, from Triple-A Sacramento.

Per Susan Slusser on Twitter:

#Athletics lose one of their three Aussies: designate Rich Thompson for assignment. Jim Miller called up with Parker, De Los Santos sent out

— Susan Slusser (@susanslusser) April 25, 2012

Thompson, 27, was claimed off waivers from the Los Angeles Angels last week. He took on just three batters during his stint with Oakland, recording a single and two outs.

The Angels DFA’d the Australian-born righty after he allowed four runs in his first 2 1/3 innings of work. Thompson earned a 3.00 ERA with 9.3 K/9 and 3.3 BB/9 in 54 innings last season. Thompson is currently out of options; he can’t be sent to the minor without first clearing waivers.

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