Kaepernick's legal team is expected to seek federal subpoenas in the coming weeks to compel testimony from Trump, Vice President Mike Pence and other officials familiar with the president's agenda on protesting NFL players, sources with knowledge of the quarterback's collusion case against the NFL told Yahoo Sports.

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.