INDIANAPOLIS —Whew.

After holding their collective breath as Houston Texans kicker Kris Brown lined up for a potential game-tying 42-yard field goal, the Indianapolis Colts could breathe a sigh of relief after that kick sailed just left up the uprights to preserve a 20-17 victory Sunday.

“We did the things we planned to do, which was go up-tempo,” Colts coach Jim Caldwell said. “It was almost like our two-minute operations to take over the game. We wanted to press the issue and be as expressive as we possibly could.”

Caldwell knew that this ride wouldn’t be easy. Not with three defensive starters, including 2007 NFL Defensive Player of the Year Bob Sanders, ruled out for the season this week. Not as the lone unbeaten squad remaining in the AFC. And certainly not facing an upstart Texans squad with designs on challenging the Colts for the AFC South title.

Knowing that a quick start offensively would give his defense a boost, Colts quarterback Peyton Manning put his offense into hyperspeed in the first quarter. In all, Manning went 19-of-25 for 176 yards — decent stats for a game for most quarterbacks, just another day at the office for the Colts’ signal caller — in the opening 15 minutes.

Those 176 yards included a 7-yard touchdown pass to Joseph Addai with 6 minutes, 20 seconds gone by in the contest. Those yards also included a 5-yard completion to Pierre Garcon that put Manning in some very exclusive company as the only quarterback in NFL history to throw for 40,000 yards in a single decade.

With Indianapolis (8-0) staked to a fast start on the scoreboard, it allowed the youthful defense the opportunity to relax and focus on making plays.

That youth movement was served quickly. On Houston’s ensuing possession, Colts rookie cornerback Jerraud Powers picked off a Matt Schaub pass to set Indianapolis up on the Texans’ 41.

The Colts drive would stall inside the 5-yard line, but a 22-yard field goal from veteran Matt Stover put the hosts up 10-0 just over 11 minutes into the contest. Stover would give Indy a 13-0 lead with a 37-yard kick early in the second quarter.

While Manning carved up the Texans defense early on, Houston’s offense found its footing incredibly difficult to locate as well. In fact, the Texans didn’t record a first down until midway through the second quarter.

By that time, Colts defensive end Dwight Freeney had already collected 1 1/2 sacks, and Indy had seemingly taken control.

“We were a little out of sync,” Texans coach Gary Kubiak said. “We script that opening, those first 15 plays, and practice them over and over again. We just made mistakes.

“We put our defense out there I think three times in a row. To put that out there, that many times, especially in this stadium, we were lucky that we were only down 10-0.”

Freeney collected his first sack on Houston’s first offensive play, setting a new Colts record with a sack in his ninth consecutive game, breaking a mark set in 2005 by teammate Robert Mathis.

The Texans finally started moving the ball late in the second quarter in an effort to get back within striking distance. Houston converted on a 4th-and-1 from the Colts’ 31 in the drive, as Schaub found standout receiver Andre Johnson for a 10-yard completion.