The signing of Parker followed news out of Raiders camp that receiver Javon Walker recently underwent a knee procedure. Oakland coach Tom Cable said he recently became aware that Walker had "follow-up" knee surgery, but the receiver is expected to be fine eventually. Walker will not participate in this weekend's minicamp.
Parker, 28, started 31 games in four seasons with the Kansas City Chiefs from 2004-07, and he caught 110 passes during that span. Last year, he bounced around to Denver, Carolina and Seattle but did not get into a game. The 5-11, 185-pound Parker was a fourth-round draft pick by the Kansas City Chiefs in 2004.
John Clayton is a senior NFL writer for ESPN.com.