HOUSTON -- Houston knew what it wanted to do — attack Miami’s suspect secondary — it just took a while to figure out how.

When the Texans finally put their passing game together, the front office was so happy with the net result, it announced a contract extension for quarterback Matt Schaub, reportedly for four years.

Schaub threw for 266 yards and one touchdown to wide receiver Andre Johnson — who looked healthy in his 39th 100-yard receiving game — in the Texans’ 30-10 win Sunday at Reliant Stadium.

“It was a great way for us to start at home,” Schaub said.

Actually, the start wasn’t great.

Timing was off

The Texans, who feature one of the NFL’s best rushing duos in running backs Arian Foster and Ben Tate, came out throwing on five of their first six plays, but the timing and rhythm weren’t there.

Schaub completed 3 of 7 passes in the first quarter; held the ball too long on two costly sacks inside the Miami 30 in the first half; and receivers Keshawn Martin and Lestar Jean dropped balls.

“Yeah, we started off sluggish. The first quarter wasn’t as planned,” wide receiver Kevin Walter said. “We have to start faster than that.”

Defensive end J.J. Watt, who batted four balls, and the Texans’ defense jumpstarted the offense in the decisive second quarter.

Schaub found Johnson for a 24-yard gain after their second pick, setting up Foster’s first touchdown run. Then, after the Dolphins’ fourth consecutive turnover, Schaub went back to Johnson for a 14-yard touchdown.

“[The defense] was able to give us a boost and help us get a little bit of momentum,” Johnson said.

‘In a great spot’

Johnson’s first scoring reception of the season came on a perfectly placed fade to the right corner of the end zone — a play he admitted the Texans don’t call enough — and the passing game had arrived.

“Matt just put the ball in a great spot,” Johnson said.

The pass was so well-placed, Dolphins cornerback Sean Smith never saw it until it was too late, despite tight coverage.

“As soon as I turned my head to look back at the ball, it was behind me,” Smith said.

The 31-year-old Johnson, who missed nine games with injuries last season, finished with eight receptions for 119 yards.

“Andre’s Andre,” Schaub said. “He’s playing at an extremely high level. He’s the best in the game, and he showed it [Sunday] — made a ton of great plays for me [and] helped me out in tough situations.”

Running on empty

The Texans stayed in rhythm in the third quarter, with Schaub completing 9 of 10 passes for 91 yards in the period, mostly on short slants, allowing them to take control despite never running effectively.

They averaged just 2.4 yards on 35 rushes.

“We didn’t run the ball [well],” Texans coach Gary Kubiak said.

Tight end Owen Daniels — the Texans’ best threat early in the game — finished with four receptions for 87 yards, and Tate had three receptions for 22 yards, as the Texans tried to keep him involved.

Schaub’s 266 passing yards were his most since Oct. 23, 2011, when he threw for 296 against Tennessee. He threw for more than 266 yards three times last season.

Most important, he didn’t turn the ball over.

“I felt really good about us throwing the ball today,” Kubiak said.

“But we’re trying like heck to keep [the Dolphins] off the field some, too, with all the snaps. I thought we threw it well; just didn’t run it very good.”