These teams averaged a combined 40 points in last season's two meetings. This game shapes up to be lower-scoring than projected, too, as these division foes are very well acquainted with each other.
The Colts have offensive line injuries. Left tackle Anthony Castonzo is out and center Ryan Kelly is questionable. Philip Rivers figures to be more game-manager than downfield attacker. The Texans are very weak versus the run so I envision the Colts eating up clock with lots of running plays and Rivers sticking to short and safe passes. 
Deshaun Watson has been on fire. But he no longer has suspended deep threat Will Fuller and hasn't dealt with a defense this good since Week 3 when the Texans faced Pittsburgh and lost, 28-21. When Fuller hasn't been in the lineup, Watson has thrown for 55 fewer yards per game and a full TD pass less.