The Ravens have traded veteran wide receiver Anquan Boldin to the San Francisco 49ers in exchange for a sixth-round draft pick, according to league sources with knowledge of the situation. Boldin, 32, was involved in a contract dispute with the Ravens, who asked him to lower his $6 million base salary by $2 million. However, Boldin declined to do so and attempts to resolve the impasse were unsuccessful. The Ravens were on the verge of releasing Boldin on Friday afternoon and he even prepared a statement thanking the fans for their support.