HOUSTON -- When he first injured his groin, Arian Foster's situation, and consequently the Houston Texans' situation at running back, seemed dire.

It shouldn't have.

Though the injury was significant, and surgery was needed to repair a muscle torn from the bone, Foster is healing much more quickly than many expected. There's even optimism from those familiar with his rehab that he'll be back on the field within the first month of the season.

Because of that, there's been less urgency for a few weeks now to get a replacement for Foster. It's one reason why the Texans haven't pounced on any potentially available running backs. Another is their faith in their existing running backs to carry them until Foster's return. The Texans could have placed Foster on injured reserve with a designation to return starting Sunday, and opted not to do that.

It's a major boon to the Texans' offense.

Since 2010, the Texans have better yards-per-rush and yards-per-pass-attempt averages with Foster in the game than without him. The numbers are especially stark in the past two seasons. With Foster, the Texans rush for 0.86 more yards per carry than without him. Over the past two seasons, they've averaged 0.66 more yards per pass attempt with him in the game.

Foster's injury often heals fairly quickly after surgery. ESPN medical expert Stephania Bell noted as much in this piece. It requires a successful surgery, which Foster's was. She added:

"Equally important to a successful outcome following this type of procedure is the postoperative rehabilitation to restore functionality. Although it might appear logical to rest what would seem to be such a delicate area, the goal is to initiate movement right away. That early movement may be basic (for example, going from lying to standing or simply active walking) but is critical for keeping muscles in the area active and preventing the buildup of excess scar tissue."

Foster has been moving again for several weeks. Last week, his brother's training facility in Houston posted a photograph of one of his sessions: