Oakland Raiders starting SLB Kamerion Wimbley might be an unrestricted free agent after all on Mar. 4.

While the Raiders technically had the option of buying back the final year of his rookie contract estimated at roughly $3.5 million, two NFL management sources told FOXSports.com that the salary could be in violation of the “30 percent rule”, which states base salaries can’t rise more than 30 percent from the previous season. This has become a particular problem in rookie deals. The only true way around this issue is giving players huge signing bonuses, which are not subject to the rule.

Wimbley’s base salary for the 2010 season was $2.115, so a 30 percent increase would bring the salary to roughly $2.75 million. The final year of his deal, at $635,000, voided because he met minimum playing time.

Wimbley’s agent, Joe Linta, did not return calls seeking comment for this story.