Emmitt Smith went entire NFL preseasons without touching the football in a game. Barry Sanders would get one or two carries in a preseason game and call it a night.

Arian Foster doesn't have that luxury — not with Gary Kubiak as his coach. Kubiak believes in playing his stars plenty in the preseason. And that philosophy is in danger of crippling the Houston Texans when the games actually do count.

The Texans are already flirting with preseason disaster in San Francisco, with Foster — the lifeline running back who racked up 2,220 total yards last season, tops in the NFL — limping into the locker room after a carry late in the first quarter of preseason game No. 3 Saturday night. As soon as he made a cut on a play, it was obvious that Foster had hurt something. He hobbled/stalked off the field in obvious disgust, ripping off the tape around his leg and flinging his helmet.

Soon, he was heading for the locker room.

The early report from the team is that Foster hurt his hamstring, the same hamstring that bothered him early in camp and caused him to miss the Texans' preseason opener against the New York Jets. There are still 14 days before the Texans take the field in a game that means anything (Sept. 11 vs. the Indianapolis Colts at Reliant Stadium), 14 days to recover.

"I think Arian Foster's going to be all right," Texans owner Bob McNair said in an on-air interview on KTRK Ch. 13 in the fourth quarter of its game broadcast. "He pulled the hamstring. But I don't think it's going to be severe."

If it is a minor hamstring issue, you'd think Foster has enough time.

But why are the Texans even risking it? Foster hurt himself on his eighth carry of the first quarter (in a preseason game!) This after Foster touched the ball six times against the New Orleans Saints in preseason game two and looked great doing it, looked more than ready for the regular season in fact.

Yet, Kubiak kept feeding the ball to Foster in the first quarter in that Northern California sunlight (the back had nine touches overall, adding a catch) like the coach thought that moving to 3-0 in the preseason actually means something. There's a difference between playing preseason games with urgency (as the better teams like the New England Patriots and Green Packers do) and playing them with stupidity.

By continuing to let Foster get carry after carry against the 49ers, Kubiak came awfully close to crossing that line.

This isn't a second guess either. I wrote about Kubiak's maddening penchant for overplaying his starters in the preseason last August when he left Andre Johnson in a meaningless game far too long (the same Johnson who ended up battling injuries the entire 2010 season) and again before the Texans' second preseason game this year.

"It shows why you're going to need three good running backs," McNair said on the KTRK broadcast. It also shows why you need a smart coach. Sound decision making 101, Bob?

Even rookie 49ers coach Jim Harbaugh knows enough not to play his starters a ton in the third preseason game. Harbaugh lifted his first teamers before Kubiak did and San Francisco is going to be an absolutely horrible team with nothing to play for this year (bad enough that Harbaugh will have a good shot at drafting his old Stanford quarterback Andrew Luck with the No. 1 overall next April).

San Francisco has little to protect its players for and yet Harbaugh practiced caution. That's what you do. You don't waste your bullets in the preseason.

Houston has everything to play for (the AFC South title and the franchise's first playoff berth is right there for the taking) and yet Kubiak still couldn't help himself from coaching an exhibition everyone would have forgotten about by Wednesday (if Foster hadn't gotten hurt) with wild abandon.

Maybe Kubiak's strengths as an offensive wizard (he's turned the Texans into one of the most feared offenses in the league without anything close to a legitimate No. 2 wide receiver) make up for his inexplicable risk taking in the preseason. The problem is you just never know when this coaching tic is going to endanger the regular season.

Dark Cloud on a Sunny Day

The Texans' first-team offense dominated once again (building up a 24-7 lead on way to a 30-7 win), Wade Phillips' defense is looking opportunistic, Matt Schaub shrugged off throwing a pick-6 in the game's first nine seconds and backup tailback Ben Tate looks good (if not as spectacular) again. But none of this matters if Foster is out for any length of time.

There will be a lot of talk about Foster's injury being a fluke that could have happened anytime. Don't buy it. He isn't running with the same intensity in practice that he is in a preseason game. There also isn't anyone trying to tackle him.

This might be funny if it only freaked out the fantasy football dorks who have Foster No. 1 on their "draft boards." But this affects real football. If Foster's hamstring trouble lingers, all the hope the Texans built up this preseason — from J.J. Watt to James Casey to Owen Daniels to Tate — could all be for naught.

"We have quite a few guys nicked up," Kubiak said in his halftime TV interview. "We'll take a look at some young guys now."

Too late.

Foster had already taken a frightening leap on an early run against the 49ers Saturday night before that fateful eighth carry. Kubiak still needed to see more of No. 23 after that? Why?

It's a question the coach had better hope he's not asking himself in private all season. Hamstrings are a tricky business. Coaching preseason football isn't. Or shouldn't be.

It's a shame Kubiak had to make it complicated.

To hear what Kubiak has to stay on Foster's status for the season opener against the Colts, read the CultureMap story.