It wouldn't be a Dallas Cowboys offseason without at least a few major contract disputes. David Moore of the Dallas Morning News reported on Monday that the Cowboys' All-Pro guard Zack Martin was not aboard the team charter flight to training camp that left Dallas that morning.

Martin's displeasure with his current compensation became known late this offseason. Reports started rolling in shortly before training camp that the veteran lineman could potentially sit out if the Cowboys' front office wasn't willing to restructure his contract.

With the team plane now officially departed for Southern California without Martin aboard, that possibility looks a little bit more like reality.

However, Martin hasn't missed the boat just yet. The Cowboys' charter flight to the west coast that left on Monday was not mandatory and players have until Tuesday to officially report to Oxnard for training camp. As long as Martin makes his way to SoCal by then, he won't be an official absence.

The contract dispute between Martin and the Cowboys is over Martin's pay in relation to some of the other top guards in the league. Martin is set to make just over $13 million in average annual value this year according to Spotrac. Quenton Nelson of the Indianapolis Colts will make upwards of $20 million in AAV this season.

Only time will tell what Martin's involvement will be in training camp if the Cowboys choose not to restructure him. If Martin sits out of training camp entirely, he stands to lose around $1 million in fines, Fox Sports contributor David Helman noted in a tweet on Monday afternoon.