Richardson has not practiced this week after self-reporting a concussion in the second quarter of Sunday’s win over the Houston Texans.
With Richardson out, Gardner Minshew will make his first start for the Colts.
A source told ESPN’s Jeremy Fowler that Richardson is optimistic about playing in Week 4 against the Los Angeles Rams, assuming he passes through the protocol. The Colts and Richardson have been cautious this week in their discussions about his return.
Richardson had scored rushing touchdowns on consecutive offensive plays for the Colts during Sunday’s 31-20 win over the Texans, before admitting he was experiencing concussion symptoms early in the second quarter and being removed from the game.
Minshew entered for Richardson and threw for 171 yards on 19-of-23 passing with a touchdown and zero interceptions. Minshew is starting for the first time since Week 17 last season for the Philadelphia Eagles.
Center Ryan Kelly, who is in the concussion protocol, will not play Sunday either.