Green Bay Packers running back Ty Montgomery was an unexpected spectator during Tuesday’s training camp practice.

UPDATE: Montgomery missed Tuesday’s practice because of a lower leg injury, according to Rob Demovsky of ESPN.

He wasn’t known to be injured during last week’s preseason opener, but Montgomery still wasn’t in pads for the Packers’ first public practice since Green Bay’s 24-9 win over the Philadelphia Eagles:

The Packers held a closed practice on Sunday, making it possible Montgomery was injured during the weekend.

He carried three times for zero yards and a fumble in his preseason debut against the Eagles.

Montgomery did not appear to be wearing any kind of protective device while spectating Tuesday’s practice. No additional information is currently known about his injury, although that should change following the practice.

Also, Packers coach Mike McCarthy will speak with the media on Wednesday morning. He should be able to provide an update tomorrow.

With Montgomery out, rookie Jamaal Williams got the first snaps with the starting offense. He is the clear-cut No. 2 running back behind Montgomery.