GREEN BAY, Wis. -- On a weekend when one of their all-time great quarterbacks will be celebrated and their current quarterback is expected to be a spectator, the Green Bay Packers are likely to play the Pro Football Hall of Fame Game with two undrafted, rookie, free-agent quarterbacks: Joe Callahan and Marquise Williams.

Unless, of course, Brett Favre wants to take off his new gold jacket and don his now-retired, green-and-gold No. 4 for one more night.

Brett Hundley, the Packers' No. 2 quarterback, sat out his second straight practice Thursday night with an ankle injury, putting his status for Sunday's game in doubt. And although Packers coach Mike McCarthy has not officially said whether two-time NFL MVP Aaron Rodgers will sit out Sunday's game against the Indianapolis Colts, Rodgers was given the night off from practice Thursday, a telltale sign that he will not play.

Last year, the Minnesota Vikings' Teddy Bridgewater and the Pittsburgh Steelers' Ben Roethlisberger did not play in the Hall of Fame Game, and Rodgers didn't sound like he was expecting to play when he spoke with reporters earlier in the week.

Rookie quarterback Joe Callahan is likely to start for the Packers in the Hall of Fame Game if Aaron Rodgers and Brett Hundley sit out. Courtesy Packers.com

"If I'm not playing -- and I haven't played a ton in the preseason the last couple years -- I'm on the headset, I'm listening to the plays, I'm helping [Hundley] out, and I'll be there for Joe and Marquise as well," Rodgers said. "I stay dialed into the game.

"I'll enjoy some laughs when the defense is out there, but I'll be watching the game, for sure. When the guys from my room are out there playing, I'm going to be involved in what they're doing and talking to them when they're coming off the side and making sure that they're seeing the right things and feeling good about the progressions."

If Rodgers sits out and Hundley can't go, Callahan would probably start, because he has worked as the No. 3 quarterback since signing with the Packers after the draft. Williams would then relieve him, having not joined the team until three weeks after Callahan in May.

"I think you have to be ready for the alternative," McCarthy said before practice. "The two young quarterback were going to play a lot anyway going into it, and the game plan for offense will reflect that.

"That's the way it goes."

Callahan, who is 6-foot-1, 216 pounds, had a record-setting career at Division III Wesley College, a liberal arts school in Dover, Delaware. As a senior last season, he threw for 5,063 yards and 55 touchdowns en route to the Gagliardi Trophy, awarded to the best player in Division III. The Packers were the lone team to show interest in him before the draft.

"I'm going to prepare for as many plays as they give me and make sure that I prepare as much as possible," Callahan said before Thursday's practice.

Williams, a 6-foot-2, 220-pound quarterback, left North Carolina after having set more than 20 school records, including career rushing yards (2,458) and touchdowns (35) by a quarterback.

"Marquise has really picked up, and Joe's done a very good job of improving," McCarthy said.

Colts coach Chuck Pagano said Monday that he plans to play quarterback Andrew Luck and the rest of his healthy players, though Pagano hasn't said how long his starters will play. McCarthy said throughout the offseason that Hundley would get extended work during the Packers' five preseason games, having been promoted after serving as the Packers' No. 3 quarterback as a rookie last season behind Rodgers and Scott Tolzien, who now backs up Luck with the Colts.

Hundley, a fifth-round pick from UCLA last year, was magnificent in preseason last summer, completing 45 of 65 passes for 630 yards with an NFL-best seven touchdown passes and a passer rating of 129.7, the second highest in the 2015 preseason.

McCarthy said before practice that he and his staff would have their playing-time meeting Friday morning after getting the medical report from head athletic trainer Bryan Engel and team physician Dr. Pat McKenzie. But it looks as if it'll be the Callahan and Williams Show on ESPN on Sunday night.

"First time, on national TV, so this will be pretty cool," Callahan said. "It's exciting. I can't wait."

Meanwhile, Packers running back Eddie Lacy, who dropped out of practice Wednesday night with an ankle injury, watched practice Thursday night. He appears unlikely to play as well.