There were two notable players absent from the 49ers' training camp practice on Wednesday in Santa Clara.
Both star wide receiver Brandon Aiyuk and All-Pro left tackle Trent Williams did not participate in the early portion of practice available to the media.
Coach Kyle Shanahan confirmed to reporters Wednesday that Williams' absence is contract-related.
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ESPN's Jeremy Fowler reported on June 9 that Williams "eventually" will want a reworked contract.
Aiyuk was on hand for practice but watched from the sidelines in street clothes before appearing to leave the field with 49ers president of football operations and general manager John Lynch, according to The Athletic's Matt Barrows.
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Aiyuk showed up to the 49ers facility on Tuesday after reportedly requesting a trade from the team on July 16 amid ongoing contract negotiations.
With Aiyuk's situation still in limbo, the 49ers might be forced to pay another one of their star players in Williams soon.