INDIANAPOLIS -- If backup quarterback Charlie Whitehurst ends up playing for the Indianapolis Colts in the remaining four games, it would mark the first time since 2011 the team had three quarterbacks start games.
With Luck and now Hasselbeck both disappointing and injured, the Colts are not sure who will start Sunday at Jacksonville -- or for the rest of the season.
Hasselbeck was 4-0 as a backup taking over as a starter this season, but struggled mightily and was injured in the loss to the Steelers Sunday night.
"We didn't handle their blitz early really well," Hasselbeck said. "We knew it was coming and we didn't handle it and they would just rush three. They did a really nice job of keeping off balance. I'm very disappointed in how I played. Extremely disappointed."
Hasselbeck (neck/shoulder) has been diagnosed with a sore, stiff neck and a mild rib separation. He underwent an MRI exam after the game.
He is expected to participate in Wednesday's practice and his availability for Sunday's game at Jacksonville will be determined at the end of the week.
Luck (kidney/abdominal) resumed throwing over the last couple of weeks. Luck's throwing regimen has increased recently, although he has yet to be cleared to fully participate in a practice session.
No time has been given as to when Luck is expected to resume practice or be able to play in a game.
--Wasted opportunities. The Colts scored only 10 points in six red-zone opportunities against Pittsburgh on Sunday night.
--The Colts are 15-0 against the AFC South since the start of the 2013 season. But Indianapolis is 13-16 against the rest of the NFL over that 44-game regular-season schedule.
--If the AFC playoffs were to begin today, the Colts would be the No. 4 overall seed.
--Head coach Chuck Pagano was pretty succinct in describing what happened in the Colts' 45-10 road loss to Pittsburgh Sunday night.
"I give credit to the Steelers," Pagano said. "They played well in all three phases. They kicked our ass. Period. We had some opportunities early in that ball game and we did not capitalize on those. We don't have a lot of time to sit and dwell on this. It stinks. But we have to move on."
--Safety Colt Anderson (ankle) was hurt against Pittsburgh on Sunday night. Anderson is expected to be week-to-week. He has been used as a backup starter filling in for Mike Adams and as a special teams performer. Anderson has been one of the Colts' best special teams members the last couple of seasons.
--Inside linebacker Nate Irving (wrist) is expected to be listed as week-to-week in practice after he was hurt in the Steelers game on Sunday night. Irving started against Pittsburgh, filling in for injured starter Jerrell Freeman. He had been nursing a surgically-repaired knee since the start of training camp, but had seen increased playing time in recent games.
--Inside linebacker Jerrell Freeman (hamstring) remains listed as week-to-week with a Grade 2 strain. Freeman was injured against Tampa Bay two games ago and has yet to practice since he incurred the injury. He is not expected to be available Sunday when the Colts play at AFC South rival Jacksonville.
--Guard Hugh Thornton (elbow) was held out of the Pittsburgh game after he was dinged up against Tampa Bay two weeks ago. Thornton did not go through practice last week. He is expected to return for workouts on Wednesday. Thornton is hoping to be cleared to start against Jacksonville on Sunday.
--Offensive tackle Anthony Castonzo (knee) has made improvement since he has been sidelined because of an MCL sprain. He was hurt against Atlanta three weeks ago. Castonzo is not expected to be cleared to play in time for Sunday's trip to Jacksonville. He remains listed as week-to-week.
--Rookie wide receiver Phillip Dorsett (fibula) should be given the OK to resume practice on Wednesday. Dorsett has been sidelined for the last month. He was cleared to ramp up rehab practice in the last couple of weeks. Dorsett should return to practice this week but his availability for the Jacksonville game on Sunday has yet to be determined.