Sterling was responding to a May 14 letter sent by Buchanan informing him that he must pay the $2.5 million fine.
Blecher also said Sterling's actions do not merit any kind of punishment, that his client's due process rights were violated and that the controversy "will be adjudicated."
Silver banned Sterling for life from the NBA and fined him for his racial comments to a female assistant that were first exposed by TMZ. Silver also asked the league's team owners to vote to force a sale of the Clippers.
In an interview with CNN's Anderson Cooper on Monday, Sterling said he "made a terrible, terrible mistake" with his racial comments in his attempt at an apology. Sterling's wife, Shelly, also has expressed her willingness to fight to retain her stake in the team.
Blecher, an anti-trust lawyer, previously represented Sterling when the Clippers planned to move from San Diego to Los Angeles and also served as a lead attorney in the Los Angeles Memorial Coliseum's successful antitrust suit against the NFL.