Ugoh has missed the last two games with a neck injury, but had returned to practice this week and wasn't added to the official injury report until Saturday, when he was listed as doubtful. The rookie started at left tackle as Peyton Manning's blind-side protector -- a position left even thinner with the ankle injury suffered by backup Charlie Johnson last Sunday against San Diego.
Harrison, who has missed the last three games with a knee injury, did not practice on Wednesday or Thursday and was listed as questionable on the injury report.
Klecko's touchdown reception on a goal-line play helped rally the Colts from a 21-6 halftime deficit in their AFC Championship Game victory over New England in January.
Klecko re-signed with the Colts in March, but was limited to two tackles in three games this season.
The Associated Press contributed to this report.