HOUSTON — In a pair of moments, many of the good feelings the Panthers generated in an undefeated start went away.

And now they have to wonder when they might return.

The Panthers beat the Texans 24-9 Thursday night to improve to 3-0, but everything pales considering a couple of injuries that could change the course of a season.

Christian McCaffrey left early in the second quarter with a hamstring injury and didn't return, and rookie cornerback Jaycee Horn left in the third quarter with a foot injury and was carted off the field. Afterward, Panthers head coach Matt Rhule didn't offer any timetables on either injury, but said Horn "broke some bones" in his foot.

McCaffrey spent 20 minutes in the medical tent before walking slowly to the locker room.

At the time, the Panthers led 7-0, and were handling the Texans with the same kind of pressure they showed in the first two games.

Before a last-minute-of-the-half touchdown drive, they had held the Texans to 44 yards of total offense, and it didn't seem like that many. But rookie quarterback Davis Mills found Anthony Miller for a touchdown, and former Panthers kicker Joey Slye missed the extra point, allowing the Panthers to limp into the half with a 7-6 lead.

Those were the first points the Panthers allowed in a first half this season.

When Horn was carted off, after a non-contact injury, it made a bad night even worse.

The first-round pick was in immediate pain, and had to be helped off the field by two members of the athletic training staff. The Panthers were already without veteran cornerback A.J. Bouye, who was inactive after coming back from his suspension four days ago.

Veteran safety Juston Burris also left with a groin injury, suffered two plays before Horn's.

— It would not be wrong to say the wheels fell off the Panthers offense when McCaffrey left the game.

On the 11 plays in the first half after his early exit, they managed 14 net yards.

The pass protection grew leaky (three sacks), and Sam Darnold lost the ball twice (both fortunately recovered by center Matt Paradis).

To its credit, the offense stabilized in the second half, led by a steady Darnold, who went 10-of-13 for 146 yards in the final two quarters.

— The Panthers got unconventional on their second score, with Royce Freeman's first carry as a Panther going for 13 yards, followed by Darnold hitting Alex Erickson for a 25-yard pass, and it then got weirder.

Tight end Tommy Tremble took a quick jet sweep run 7 yards for a touchdown, giving the Panthers some breathing room.

It's the kind of diversity of offense they're going to need if McCaffrey misses time.

— The Panthers continued to play stifling defense, with four more sacks. They held the Texans to 193 yards, and they entered the night ranked first in the league in points and yards allowed (and sacks and a lot of other stuff).

Obviously things will get tougher if the injuries mount, but the Panthers were able do what they needed to Thursday, as Pyrrhic a win as it might have been.