They had failed three times in four chances when facing third- or fourth-and-1 earlier in the game, including on the previous play.
They could have attempted a 51-yard field goal with a kicker, Josh Brown, who had made all three attempts in this game. Brown has also hit 15 of 19 field goals from 50-plus yards since signing with St. Louis.
But if Steven Jackson could reach that first-down marker, the Rams would be in position to take time off the clock before attempting the winning field goal from a shorter distance.
Coach Steve Spagnuolo's decision to go for it backfired when the Cardinals prevented Jackson from adding to his 104-yard rushing total to that point in the game. The Rams wound up getting a second chance as regulation expired, but the Cardinals' Calais Campbell blocked their 42-yard attempt, forcing overtime.
And we all know what happened there.
Jackson has now failed to convert a first down on four consecutive rushing plays when the Rams needed one yard on third or fourth downs. Fullback Brit Miller converted once in two such situations Sunday.
"I felt confident in our best football player getting the ball," Spagnuolo told reporters after the game. "There was still time there, they had no timeouts. I was looking to finish the game on a field goal to win. ... Defensively, we had just come off of a series where we were a little bit tired, a little bit worn down. In hindsight, maybe it was a bad decision."
The decision to run additional time off the clock would have made more sense to me if Kurt Warner or another top quarterback were leading the Cardinals' offense. But with John Skelton starting for the fifth time in his career, Arizona did not seem to present an immediate threat. Then again, Spagnuolo had to know the Cardinals were vulnerable against short-yardage rushing plays, having allowed six conversions in eight chances on third-and-1 before Sunday (Arizona's previous opponents had not carried the ball on fourth-and-1).
Hank Gargiulo of ESPN Stats & Information crunched win-probability numbers for the fourth-and-1 decision and concluded neither choice presented a clear advantage.
The numbers favored Spagnuolo's decision over attempting the field goal, 68.8 percent to 62.2 percent, when plugging in Jackson's career conversion rate on fourth-and-1 (80 percent) and Brown's career rate for 50-plus field-goal tries (68.3 percent). But if we paired the NFL average for fourth-and-1 conversions (70 percent) with Brown's 50-plus percentage as a Ram (78.9 percent), the numbers would favor the field goal, 67 percent to 64.3 percent.
Those percentages aren't compelling enough to outweigh all the variables a coach considers when making such a decision. But the Rams' recent short-yardage failures, the presence of an unproven quarterback on the other team, favorable conditions, Brown's solid kicking Sunday and Brown's career percentage from long range would have led me to favor the field-goal try.
The chart lists the Rams' third- and fourth-and-1 rushing plays this season, including what personnel they used on those plays.