CBS Sports is reporting that lawyers for former San Francisco 49ers quarterback Colin Kaepernick will reportedly seek to subpoena President Trump in an alleged NFL collusion case. 

His lawyers claim that the president and NFL team owners illegally colluded together to prevent Colin from ever entering the league.

Midway through the 2017 season Kaepernick had filed a collusion grievance against the NFL, and last month, Pro Football Talk reported that "internal franchise documents generated as part of the free-agency evaluation process and testimony from witnesses harvested via depositions in the collusion litigation has established that teams viewed Kaepernick as being good enough not simply to be employed by an NFL team, but to be a starting quarterback for an NFL team."

CBS Sports says the aim will be a dive into the administration's political involvement with the NFL during Kaepernick's free agency and the league's handling of player protests, sources said. This after recent disclosures that multiple owners had direct talks with Trump about players kneeling during the national anthem. The content of those conversations between Trump and owners -- as well as any forms of pressure directed at the league by the administration -- are expected to shape the requests to force the testimony of Trump, Pence and other affiliated officials, sources said.

First, the NFL's system arbitrator has to decide that such depositions are justified. Then, a federal court has to issue -- and enforce -- the subpoena requests. Then there's the matter of whether a sitting president can be compelled to sit for a deposition. 

Kaepernick hasn't played in the NFL since Jan. 1, 2017. The Seahawks expressed some interest in him in April, but nothing has come of it. Meanwhile, Kaepernick's former teammate, safety Eric Reid, who also remains unsigned after participating in the protests, filed his own collusion grievance earlier in May. 

(CBS Sports contributed to this report.)