Foxborough, Mass. — One of the biggest questions for the Patriots entering the season was how their defense would look following a series of offseason tweaks.

While the defense certainly had some miscues during New England's 27-20 victory over Houston on Sunday, it may not be the unit looking to make the most improvement heading into Week 2.

That task probably belongs to special teams, which had several mistakes that allowed the Texans to stay within striking distance for most of the game.

Special teams has been one of the Patriots' most stable areas the past few seasons. But against Houston the unit showed cracks in both kickoff coverage and punt return. Improvement will be key with a tough road matchup at Jacksonville up next.

Last season, the Patriots allowed opponents just 18.9 yards per kickoff return, the third-best mark in the NFL.

That meant nothing to Houston's Tyler Ervin, who found all kinds of seams in New England's kickoff coverage. He finished the game with 156 kickoff return yards on five returns (31.2 avg.), including a game-long 36-yard return.

The 156 return yards are the most ever by a Texans player in a season opener.

"I thought there were a lot of areas that we did well in, a lot of areas that we need to work on and a lot of areas that we can improve," coach Bill Belichick said when asked about the mishaps on kickoffs.

Special teams captain Matt Slater said he didn't think the new kickoff rules aimed at improving safety were to blame for their deficiencies.

"I think it was more about what we didn't do," he said. "Some of the things that we're coached to do we just didn't go out there and do them. ... It plays differently, obviously there's no wedges. Schemes have changed a little bit. But hopefully it's something we can fix."

New England's punt team wasn't exempt from mistakes, either.

With under five minutes left in the game, Riley McCarron fumbled a punt to set up Deshaun Watson's 5-yard touchdown pass to Bruce Ellington that got the Texans within seven.

"I made a stupid play," McCarron said. "I should have handled the ball; it is as simple as that. I did not make the decision on a fair catch, obviously, but I know the one I should have made now."

McCarron was released by the team on Monday.

It wasn't all bad for the special teams.

Before he suffered a right knee injury in the third quarter, running back Jeremy Hill partially blocked a punt by Houston's Trevor Daniel.

And some late execution by the Patriots' punt coverage team helped put a slight happy face on an otherwise lackluster day.

The play came via punter Ryan Allen, who dropped a 54-yard punt inside the Houston 5, which was downed by Jonathan Jones on the 1 with 43 seconds remaining. It forced the Texans to speed up on offense and they moved the ball to only their 43 by game's end.

Slater said both Hill's block and Allen's punt were shown a lot in Monday's film session. Still, there was little celebrating.

"The hits keep coming," Slater said. "This will be a tough team this week and we gotta be on top of our game and certainly try to execute better."

NOTES: The team placed Hill, who reported suffered a torn ACL on that third-quarter play, on the season-ending injured reserve list. Hill's 2017 season with Cincinnati ended after seven games, when he had right ankle surgery. ... Hill entered the season third on the running back depth chart behind James White and Rex Burkhead and was expected to contribute primarily on special teams. ... The team also released wide receiver Chad Hansen.