INDIANAPOLIS — The right side of the offensive line — particularly the right tackle position — will remain up in the air for the Indianapolis Colts up until their regular season opener against the Cincinnati Bengals.

But we at least know now who will get first crack at those spots in Thursday's final preseason audition (which also happens to be against the Bengals).

Colts head coach Frank Reich said Tuesday that rookie Braden Smith will start at right guard in Thursday's preseason Week 4 matchup at Paul Brown Stadium, while third-year veteran Joe Haeg gets the start at right tackle.

Other players vying for that starting right tackle job include Austin Howard, J'Marcus Webb, Tyreek Burwell, Smith, Le'Raven Clark and Mark Glowinski. Denzelle Good also remains in the mix, although he suffered a knee injury in Saturday's preseason contest against the San Francisco 49ers and is considered "week-to-week."

Smith, meanwhile, remains in competition with veteran Matt Slauson for the starter's job at right guard, Reich said.

So, as of Tuesday, we know of the starters for this week's game at:

» Quarterback: Jacoby Brissett

» Running back: Robert Turbin

» Right guard: Braden Smith

» Right tackle: Joe Haeg

Here are a few other observations and notes from Tuesday's practice and media availability:

— Those either not out on the field or not participating were quarterback Andrew Luck (foot), wide receiver K.J. Brent (knee), wide receiver James Wright (knee), safety Ronald Martin (shoulder), cornerback Kenny Moore II (rest), running back Marlon Mack (hamstring), safety Clayton Geathers (rest), cornerback Nate Hairston (hamstring), cornerback Quincy Wilson (hand), safety T.J. Green (hamstring), tight end Darrell Daniels (shoulder), linebacker Anthony Walker (groin), linebacker Darius Leonard (lower leg), linebacker Jeremiah George (back), tackle/guard Denzelle Good (knee), tackle Anthony Castonzo (hamstring), wide receiver Krishawn Hogan (unknown), defensive tackle/end Tyquan Lewis (foot), defensive tackle/end Denico Autry (ankle) and defensive end Anthony Johnson (back).

— Reich said Luck, who injured his foot after being tackled from behind while scrambling during the second quarter of Saturday's game against the 49ers, "will be there at practice on Monday and ready to go" as the team officially begins its preparations for its regular season opener.

— As for Wilson, Reich said he's "hopeful" the second-year cornerback is able to return to practice next week. Wilson suffered a hand injury during practice last week and did not play against the 49ers.

— Autry is "making good progress" from an ankle injury suffered in the second preseason game against the Baltimore Ravens, and Reich believes he'll be ready to go to start the season.

— Then there's the hamstring injuries to two key offensive players: starting left tackle Anthony Castonzo and running back Marlon Mack. While both have been out several weeks now, Reich said both have seemed to show positive signs the last couple days particularly. Reich has said he believes Castonzo should be ready to go by Week 1, as long as he can get some practice in before the game; Mack's status is a little bit more in the air, however.

— Reich confirmed center Ryan Kelly and left guard Quenton Nelson will not play Thursday in the preseason finale. We already knew a good number of the Colts' starters will not play in this game.