Entering Sunday's game against the Bears, the 29-year-old Williams has just eight rushing attempts in the last two games for 10 yards. He carried the ball 11 times for 33 yards in the Panthers' 23-22 loss at Chicago.
For the season, he has rushed for 210 yards on 61 attempts and two touchdowns.
The biggest obstacle to any Williams trade is his contract. His $5.25 million salary this season is guaranteed, meaning any team that trades for him would be on the hook for $2.6 million in the second half of the season.
But that's still considerably less than the $19.5 million that Williams made last season, after he signed an extension that after this year still has three more seasons and $18 million on it.
Those figures would make Williams the 14th highest-paid running back in the league, but it could be a price a running back-needy team would be willing to pay by Tuesday's trade deadline.