The Texans fell to 1-2 after the third-round pick threw just one touchdown pass, a one-yard completion to a wide-open Anthony Miller in the second quarter.
Mills completed 19-of-28 passes for 168 yards and a touchdown in the loss.
Through two weeks, three rookie quarterbacks -- Zach Wilson (New York Jets), Trevor Lawrence (Jacksonville Jaguars) and Justin Fields (Chicago Bears) -- have struggled at times. New England Patriots quarterback Mac Jones has had the most success, but he’s been more of a game manager with just one passing touchdown heading into Week 3.
Earlier in the week, coach David Culley said the Texans would make sure to help the rookie.
“We know he's a rookie quarterback, but we'll help him out and we'll do things to make sure that all other 10 guys around him are doing their job to be able to keep him upright and keep him comfortable,” Culley said.
QB breakdown: One area Mills struggled in during the preseason was being able to take care of the football. Culley stressed the importance of some more consistency without throwing an interception, and Mills was able to do that Thursday.
Mills is the seventh rookie quarterback since 1970 to make his first career NFL start against the team that was leading the league in points allowed per game and yards allowed per game, according to Elias Sports Bureau.
Promising trend: Despite the change in quarterback, wide receiver Brandin Cooks continued his strong start to the season with nine catches for 112 yards. Cooks is only the second Texans player in franchise history with more than 300 receiving yards through three games. Wide receiver Andre Johnson also hit that mark in 2006 and 2011.
Biggest hole in the game plan: The Texans’ running game never really got started, with five players combining for 42 yards on 17 attempts. Mark Ingram led the way with 21 yards on six carries, but Houston’s longest rushing play of the game was seven yards. It won’t get any easier in Week 4, as Buffalo Bills enter Week 3 allowing an average of just 73 yards per game, which is the seventh-best in the NFL.