Gordon informed the Chargers that unless he receives a new contract, he will demand a trade and will not report to training camp, NFL Network's Tom Pelissero reported.
ESPN first reported the news.
Gordon would be subject to fines of up to $40,000 for each day missed if he does not report, per the collective bargaining agreement.
Damarius Bilbo, one of the agents who reps Gordon, told NFL Network Insider Ian Rapoport that the running back is serious about holding out.
"He's very serious," Bilbo said. "He's worked his butt off and the fifth-year option is a result of where he was drafted. It's what it is. But if we'd gotten a respectable offer, we wouldn't be here. But he felt disrespected. He's very serious."
Gordon is entering the fifth and final year of his rookie contract, set to earn $5.6 million. He wants the security that comes with guaranteed money on a long-term deal. His 2019 salary is the 11th highest among running backs for this season. The 26-year-old likely looks at the list and sees a whole lot of backs used less than himself and who aren't as vital to a team's offensive operation getting paid more.
"We received an offer -- talks had been dead -- but we received an offer that wasn't a fair offer based on what Melvin has done, where he was drafted, and how he's performed, making two of the last four Pro Bowls," Bilbo said. "It was disrespectful."
The do-it-all back has been a keystone piece of the Chargers offense since his second year in the league, compiling more than 1,300 scrimmage yards each of the past three seasons, with 38 total touchdowns. Gordon proved his worth to the L.A. offense last season while dealing with knee issues. The Chargers offense wasn't the same without the bruising back at full threat-level.
The 2015 first-round pick skipped most of the offseason workouts, but attended mandatory minicamp in June, where he said "I don't know," when asked if he'd hold out of training camp without a new contract.
It's conceivable a holdout could stretch into the regular season.
"We'll cross that bridge when we get there," Bilbo told Rapoport when asked if he'd sit out regular-season games. "If Melvin is not paid fairly, he will want to be traded."
It's possible the situation across town with Todd Gurley's knee could give the Chargers pause to pay Gordon. The Rams handed Gurley a pile of money and now are dealing with a back that could have chronic knee issues. Given Gordon's injury history, the Chargers might be reticent to hand their back a ton of guarantees.
"It's an issue with everybody else," Gordon said. "But I know my value. I know what I bring to this team, and I'm sticking with that. Todd's paid, so Todd don't care what anybody says right now -- him or David Johnson -- they can say what they want to say. They signed the dotted line.
"But unfortunately I haven't yet, so I've got to take the heat for some of the stuff that they're going through. But I'm not them, and like I said, I know my value."
The dual-threat back knows his value. He's willing to hold out and demand a trade to someone who will compensate him as such, if the Chargers won't.
Not having Gordon would be a massive blow to the L.A. offense, one that looks poised to compete for a deep playoff run. But paying running backs in 2019 can be a precarious proposition for NFL teams.
Gordon's only leverage to get the deal he desires is to withhold his services. The running back is preparing to do so.