Lynch, who had his own contract issues with the Seahawks in the past, sported the blue practice jersey even though the offense was wearing white during preparations for Sunday's season opener at St. Louis.
Chancellor posted a picture of Lynch in his uniform to Instagram and thanked Lynch for the support.
Defensive coordinator Kris Richard said Lynch's gesture was ''a testament to the closeness of our locker room and how much each and every single guy means to one another.''
Chancellor is in a contract dispute with the team and did not report when his teammates gathered for training camp.
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