Provo • BYU quarterback Tanner Mangum said Tuesday that the injured left ankle that caused him to miss two games in September and favor it noticeably in Friday’s game against Boise State “is definitely not 100 percent” healed.

Still, the junior is expected to start Saturday when the 1-5 Cougars travel to Starkville, Miss., to take on 3-2 Mississippi State at 61,337-seat Davis Wade Stadium. Mangum was relieved by freshman QB Joe Critchlow with 2:17 remaining Friday, a substitution that pulled Critchlow out of his redshirt season and caused speculation that the native of Franklin, Tenn., who was on a church mission less than four months ago would replace Mangum as the starter.

Whether Critchlow plays at all “just depends on how the game is going,” offensive coordinator Ty Detmer said. “If Tanner is seeing it and making the right reads and doing all the right things, then we are going to play him, the guy who gives us the best chance to win.

“And if we are not [playing well], we expect Joe to go in and play. That will be determined on the situation in the game and how Tanner is playing and all those things.”

Detmer said Mangum’s backup when the season began, sophomore Beau Hoge, “is probably going to be out another week” after suffering a concussion and an ankle injury against Utah State.

“But [Hoge] is champing at the bit to get back,” Detmer said. “When he‘s ready, the trainers and the doctors will let us know and then he will work back in.”

Critchlow spoke to reporters for the first time Tuesday and confirmed that he got a lot of reps in practice last week and was not surprised when his name was called and his redshirt yanked late in Friday’s 24-7 loss.

“I was just excited to see the field,” Critchlow said. “It has been a long time since I have played football, but I really did enjoy it. I felt the jitters, and the excitement. I am anxious to get some more playing time in, for sure.”

However, Critchlow said he doesn’t know if his insertion into the game was a signal from coaches that he will see significant playing time moving forward.

“I will prepare like I am going to play, but how many reps I will see, I am not sure,” he said.

Detmer said coaches “didn’t play [Critchlow] at the end just to waste a year for him” and stressed that Critchlow needs to be ready to play at any moment because of Mangum’s balky ankle and ineffectiveness, at times.

“That was a time in the game we felt like we could get him in and get him some reps and get some game time because it has been awhile for him and let him get that flow and the juices flowing and be ready for the next time.”

As for Mangum, who was 18 of 33 for 164 yards and two interceptions against the Broncos, he responded to internet reports that he was only 60 percent healthy before the game.

“Yeah, sure,” he said, shrugging. “I mean, it is tough to put a number on it. I don’t know where numbers come from. But yeah, it is definitely not 100 percent. But it is football. You have to learn to play through injuries sometimes and not let them serve as an excuse. I still can play. I am not going to make excuses. I can do better. Hopefully it can be better than 60, but who knows? Regardless of where it is at, I got to be sharper.”

Injury update

Defensive coordinator Ilaisa Tuiaki said linebacker Butch Pau’u, who missed the Boise State game with an injured hand or wrist, is expected to play against the Bulldogs. Tuiaki was not as high on linebacker Matt Hadley’s chances to play. Hadley missed the BSU game and no longer is listed on the depth chart. Neither is receiver Talon Shumway, who left the game with an undisclosed injury after making a catch.