Fitzpatrick was hurt on the first drive of the game Sunday when he scrambled for 12 yards and was tackled by Charles Woodson.
CBS reported during its TV broadcast that Jets coach Todd Bowles said Fitzpatrick had ''a ligament issue'' in his left thumb.
Geno Smith replaced him, seeing his first action of the season. Smith entered the summer as the starting quarterback, but had his jaw broken during training camp by a punch from then-teammate Ikemefuna Enemkpali.
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