TEMPE, Ariz. -- Four yards isn't much in football.
It's a dump pass to the running back, a bootleg by the quarterback, a slant out of the slot. Twenty-four running backs are averaging at least that this season.
But then again, four yards is a lot.
The Cardinals found out how one small play, one penalty early in a game can hold an unrelenting grip on them for an entire contest.
Arizona's drive with just more than 11 minutes in the second quarter began with the Cardinals holding a 7-6 lead and quarterback Carson Palmer a yard deep in his own end zone. Two quick runs gave the Cards a little breathing room at their 8. It was time to throw the ball. But on third-and-3, Palmer took a little too long adjusting the formation, calling receiver Andre Roberts into a quick motion. That extra step is what cost the Cards.
Palmer snapped the ball a second after the play clock hit :00. Back judge Scott Helverson threw the flag. Referee Scott Green announced the penalty, marking the ball back half the distance to the goal line.
Third-and-3 turned into third-and-7 from the Arizona 4.
Niners rookie linebacker Corey Lemonier lined up two yards back from the line of scrimmage and about a yard to the outside of left tackle Bradley Sowell. Palmer, again a yard deep in his end zone, this time in the shotgun, dropped back to pass. After three steps, Lemonier had blown by Sowell and brought Palmer down.
The Cardinals trailed 8-7.
On the ensuing free kick, Arizona punter Dave Zastudil gave the Cardinals' defense the type of room it likes to work with. San Francisco started its drive on its own 29 but on the Niners' second play, quarterback Colin Kaepernick hit tight end Vernon Davis for a 61-yard touchdown.
So what could've been anything from a long touchdown drive to a three-and-out that would've allowed Zastudil to dictate field position turned into a nine-point swing in 45 seconds.
49ers 15, Cardinals 7.
The comeback attempt
For the rest of the game, the Cardinals played catch-up, trying to overcome both big deficits -- eight points -- and small -- one and two. All because of the safety sack, which happened because of the penalty.
Arizona pulled within 15-14 right after the 49ers scored. But San Francisco had an answer, responding with another touchdown at the two-minute warning to hold a 22-14 lead going into halftime.
Every decision by coach Bruce Arians was dictated by that penalty from the moment Lemonier sacked Palmer.
The Cardinals' first drive of the third quarter was a combination of runs and passes that ate yards and clock. It was capped with a 10-yard touchdown on a corner route by wide receiver Michael Floyd, whom Palmer hit with a beautiful pass off his heels.
San Francisco 22, Arizona 20.
But instead of sending kicker Jay Feely out for the extra point, Arians opted to go for two. Actually, he didn't just decide to go for the two-point conversion, he opted for a trick play on top of it. Palmer tossed to cornerback Patrick Peterson, who circled back toward the sideline he started on. If Peterson had thrown it early, he had Larry Fitzgerald wide open. But Peterson held it too long and everyone was covered. After the game, the Niners said they prepared for the play. Arians said game flow dictated the decision to go for two.
The conversion failed. Arizona still trailed 22-20 with 8:17 left in the third quarter.
The significance of this play could be seen immediately, but it was magnified later in the game when the Niners went up by nine, a two-possession game. If the Cardinals had kicked the extra point, that would've been a one-possession game, and the pressure wouldn't have been as great to play catch-up. Instead of chasing touchdowns, Arizona could've played for field goals.
No penalty means no safety. No penalty means the Cardinals could've held on to a lead during a drive that could've ended with them ahead 14-6, and the whole game changes. No penalty means the Cardinals don't need to go for two. No safety means the Cardinals could run the ball late and avoid costly fumbles.
No penalty means the Cardinals could win in San Francisco.
All because of four yards.