Seattle Seahawks head coach Mike Macdonald called quarterback Geno Smith "probably the toughest player I've ever been around" after Smith left Sunday's 30-13 loss to the Green Bay Packers with a knee injury.

"It was severe enough for him not to come back in the game," Macdonald said. "We'll do all the tests tomorrow and kind of figure it out as we go. But right now, structurally it looks like it's OK, but we've got to get it imaged and all that stuff."

In the third quarter, Smith landed awkwardly after throwing the ball and attempting to avoid contact from Packers linebacker Edgerrin Cooper. He was unable to return, with Sam Howell taking over at quarterback.

The Seahawks didn't provide any detail about Smith's injury, only announcing mid-game he was questionable. According to NFL Network's Ian Rapoport, the two-time Pro Bowler is scheduled to have additional testing Monday.

Smith's performance has steadily dropped off since his Comeback Player of the Year campaign in 2022. While his 258.8 passing yards per game though 14 games are his second-highest ever, his 13 interceptions are also tied for his second-highest total. His 89.9 passer rating and 52.8 QBR are noticeably below their 2022 equivalents (100.9 and 62.8) as well, per Pro Football Reference.

Sunday was evidence of how badly Seattle will miss the 34-year-old if his knee injury forces him to miss time, though. Howell went 5-of-14 for 24 yards and an interception against Green Bay.

Smith's toughness isn't in question, but nobody can play through a major knee injury if that's what the testing reveals for him.