One more piece officially fell into place this morning with Romeo Crennel agreeing to a three-year deal to become the Texans' defensive coordinator.
There hasn't been much talk about who will be the Texans' offensive coordinator. It's possible the Texans don't hire one.
It would be an unconventional move if O'Brien opted to go without an offensive coordinator. There are eight other teams whose head coaches will call offensive plays. ESPN.com's Paul Kuharsky examined the trend in this piece last week. All the rest have a designated offensive coordinator. The Bears' offensive coordinator Aaron Kromer is also listed as their offensive line coach.
But consider O'Brien's history.
He took over as the offensive coordinator for the New England Patriots in 2011, but called plays before he had the title. The Patriots didn't have an offensive coordinator in 2010. The Patriots didn't have a defensive coordinator that year, either, and Bill Belichick took more responsibility on that side of the ball. This year, O'Brien will call plays for the Texans, which leaves me wondering what purpose would an offensive coordinator serve.
A coordinator might be another offensive mind with whom O'Brien could brainstorm. Sometimes teams hire give the title as a way to land an assistant they covet.
A fellow brainstormer was the role Rick Dennison served on the Texans' former coaching staff. Head coach Gary Kubiak called plays and Dennison was an old friend and coach he trusted with whom he could share ideas. There were some, though, who felt that Dennison was in over his head when he was asked to actually call plays while Kubiak was out and after Kubiak was fired.
The staff O'Brien is assembling is one that will serve that function anyway. It's possible O'Brien grooms someone from it to grow into that role.
For now, though, lacking an offensive coordinator could streamline the staff.