HOUSTON - The Indianapolis Colts lost all three AFC South road games last season.

So winning two straight this year is encouraging, even if they didn’t play as well as they’d like on Sunday.

Joseph Addai ran for two touchdowns and Adam Vinatieri added three field goals to lead the Colts (3-0) to a 30-24 win over the injury-ravaged and mistake-prone Texans to remain undefeated after beating Tennessee last week.

“As long as we’re getting the wins, we can still correct that kind of stuff,” receiver Dallas Clark said. “We’ll take advantage of it down the road. That shows you what kind of team we have here. We haven’t played great — it’s always been something here and there — but we’re still finding ways to win.”

Houston (2-1) entered the game without star receiver Andre Johnson, who sprained his knee last week, and lost running back Ahman Green to a knee injury on the first series of the second quarter. Backup Ron Dayne was inactive because of bruised ribs, so the Texans had to rely on third-stringer Samkon Gado for the rest of the game.

Rookie Jacoby Jones, who started for Johnson, left in the third quarter with a separated shoulder, and center Steve McKinney left with a knee sprain in the fourth quarter.

And defensive tackle Cedric Killings was taken off the field on a stretcher after a headfirst collision with Indianapolis receiver Roy Hall. The 310-pound Killings, playing special teams, hit Hall on a block as Jerome Mathis was returning a kickoff in the second quarter. The Texans said Killings suffered a neck injury and coach Gary Kubiak said he was moving his arms and legs and talking on the field. Killings was taken to a hospital.

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“It was a tremendous effort on everybody’s part and we paid the price for it,” Kubiak said. “We’re pretty beat up.”

Still, Houston got within 30-24 when Vonta Leach caught a 1-yard pass from Matt Schaub with 2:49 remaining in the game. The Texans got the ball back with 19 seconds left, but Schaub was sacked and time ran out.

“They played most of the game without their two best backs and then their best receiver, and they continued to fight back,” said Colts coach Tony Dungy. “We just couldn’t get that right play to knock them out of things. But we made enough plays when we needed them.”

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Houston cut the lead to 27-17 on a 1-yard run by Gado early in the fourth quarter. That score was set up by a 41-yard catch by Andre’ Davis. Vinatieri’s third field goal of the day had pushed the Colts’ lead to 30-17 in the third period.

“We marched down there and we got some scores,” Dungy said. “In the end, that was the difference. We want to come away with points. We prefer to come away with touchdowns. We did score every time we got down there. We had chances for touchdowns. We’ll get sharper and we’ll be fine.”

Schaub was 27-of-33 for 236 yards with one touchdown and two interceptions. Houston finished with just 40 yards rushing and Gado had 12 yards rushing and a fumble.

Cornerback Dunta Robinson said he was proud of how the team didn’t give up after getting down by 13 points in the fourth quarter.