The NFL Players Association has identified language in about 160 of this year's rookie contracts that it believes violates the collective bargaining agreement and is considering filing grievances to have the deals voided.

"The union has undergone a comprehensive review of rookie contracts and language in those contracts for this year," NFLPA spokesman George Atallah told ESPN on Wednesday morning. "The CBA explicitly prohibits players from some of the language that we have seen the clubs attempt to impose in these deals. We are considering all of our options to protect the players and enforce the CBA."

The union estimates that about 25 or 26 NFL teams have included some form of prohibited language in rookie contracts this year. Examples include:

Clauses that require players to submit to multiple offseason physicals at the team's request -- more than the two that are permitted under the CBA

"Automatic repayment" clauses that allow teams to directly withdraw money owed for expenses such as fines, services and tickets from players' paychecks

Language that forces prospective free agents to secure permission from their current clubs before their agents engage other teams in discussions during the pre-free agency "legal tampering" period

The NFLPA has sent letters to the NFL management council informing it of the language it believes violates the CBA.