Walker was optioned to Triple-A Norfolk on Saturday, Rich Dubroff of CSN Mid Atlantic reports.
Manager Buck Showalter was complimentary of Walker's spring training performance, but the roster needed to be trimmed down with Opening Day approaching. Walker belted four home runs and drove in 14 runs in his 42 spring training at-bats before being sent down. Dubroff reports that Walker will be the every day left fielder at Norfolk. That said, the Orioles will be trying to get by with an inexperienced Hyun-soo Kim and an injury prone Nolan Reimold in left this season, so Walker could be a prime candidate for a call-up if either of those players struggle or get injured.