The Orioles also announced Moyer will report to Triple-A Norfolk and make a start for it on Saturday.
If Moyer does make it to Baltimore, it will be his second stint with the club. He was with the Orioles for three seasons, 1993-1995.
Moyer was recently released by the Rockies after going 2-5 with a 5.70 ERA and 1.73 WHIP in 10 starts. He has 269 career wins and more than 4,000 innings pitched in the majors.
The Orioles currently have Jake Arrieta, Jason Hammel, Brian Matusz and Wei-Yin Chen firmly in their rotation, with Dana Eveland serving as a possible fill-in option. Also, Zach Britton was activated from the 60-day disabled list and optioned to Triple-A Norfolk on Friday. Moyer, Britton and Tommy Hunter could all be fifth-starter options moving forward.
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