The Colts defense has shined at times, especially at home, where they have held the Chiefs, Commanders, and Eagles to 17 points.
The Colts defense is fifth in the NFL allowing just 275.3 yards per game over their last three contests, but the offense is also the fifth lowest, averaging 273.3 yards per game over the same stretch. Even with Matt Ryan as the starter, the Colts have only topped 20 points in two of his nine starts.
On the other side, the Steelers have only topped 20 points in regulation in one game this season, which came last week.
The under is 14-2 in Colts' last 16 games overall, and the under is 6-0 in Steelers last six games after allowing more than 30 points in their previous game.
The Colts are averaging 20.6 ppg at home this season, and the Steelers are averaging 13.2 ppg on the road. I have to take the under.