The Rams trailed 24-13 entering the fourth quarter, but St. Louis managed to score 14 unanswered points in the final quarter, including a game-winning 48-yard field goal to regain the lead with under a minute left in the game.
It was an ugly victory for the Rams, but it was a victory nonetheless—their first victory in a season opener since 2006.
Every year, we believe we have a clear understanding of the team and where it stands. And every year, when the actual games are played, we're reminded of how unpredictable football truly is.
This article will cover several takeaways from St. Louis' home opener against Arizona and point out things we didn't know before Sunday's game.
You may have assumed that veteran Chris Long is the top defensive player for St. Louis after back-to-back seasons with double-digit sacks.
Or, maybe, Janoris Jenkins' four defensive touchdowns a year ago had you leaning in his direction.
The Rams have plenty of stars and rising stars on their defense, but the player with perhaps the most overall potential is Robert Quinn.
A year ago, Quinn turned in a 10.5-sack performance for his sophomore NFL season. He gained recognition as a sack artist but lived under Long's shadow.
In the 2013 opener, Quinn made a statement by sacking Carson Palmer three times and forcing two fumbles.
The secondary was getting torched and the other three members of the defensive line were quiet, but Quinn refused to back off.
Quinn is well on his way to establishing himself as St. Louis' top defensive player. If things continue, he'll be in the running for the 2013 sack title.
Danny Amendola has served as Sam Bradford's security blanket since 2010, but the Rams allowed Amendola to leave in free agency.
The Rams selected receiver Tavon Austin with the No. 8 overall pick as his replacement.
While Austin did not have any dazzling plays or jaw-dropping moments during his NFL debut, he served as a solid bailout option for Bradford out of the slot.
Austin was second on the team in receptions with six, and he picked up 41 receiving yards.
Eventually, we'll see Austin bust out a big play, but for now, we can take comfort in knowing that he's a reliable short-yardage option.
To read my grades on Austin's debut performance, click here.
In 2012, Greg Zuerlein made 13 field goals in 13 attempts to start the season, but he made just 10 of his final 18 attempts.
It appeared Zuerlein hit a mental roadblock and his accuracy was suffering, but his performance against Arizona showed us he's back on track.
Zuerlein made all four field-goal attempts, including the game-winning shot from 48 yards.
Zuerlein has now made 16 field goals in 18 attempts at the Edward Jones Dome. If his success continues, the "Greg the Leg" hype will soon return.
When Arizona went up 24-13 with a 24-yard Larry Fitzgerald touchdown, the life was completely sucked out of the Edward Jones Dome.
During those moments of apathy, the camera panned to Bradford on the sidelines. Surprisingly, he still looked cool and confidant despite the desperate situation. It appeared he was anxious to get back on the field.
He looked like a leader.
The naysayers will undoubtedly point to his fumble, as well as his interception that was taken in for a touchdown, and those are reasonable concerns—he's far from perfect.
However, he kept a level head throughout the game, and it paid off.
At the start of the fourth quarter, he led his offense downfield and hit Jared Cook for a touchdown. He followed up that play by running in a two-point conversion, which cut the deficit to three points.
Bradford led the Rams on two more field-goal drives—one to tie the game and one to give them the lead.
All in all, it's doubtful that the Bradford from a year or two ago would have done the same.
He had his share of mistakes on the field, but it's clear that putting away games is becoming a habit for Bradford, who has now won five of his last seven games.
The Rams were absolutely butchered with penalties. Frankly, the penalties kept the game closer than it should have been.
The Rams had seven total penalties for 59 yards, and many of those flags came in key situations.
On the opening drive, tackles Jake Long and Rodger Saffold were both penalized. Long's holding penalty negated a 20-yard play.
The drive should have ended in at least a field goal, but penalties cut it short.
In the fourth quarter with the game tied, Arizona punted the ball to St. Louis. The Rams were set to take over at the 10-yard line, but a taunting penalty by Eugene Sims knocked the offense back five yards before it could even take the field.
That drive went no where, and luckily, the Rams eventually got the ball back for another shot at a game-winning drive.
The Rams were constantly sabotaging themselves.
It got even worse...
Perhaps it's too early to be concerned, but the season opener was anything but ideal for Rams cornerback Cortland Finnegan.
Finnegan was burned in the end zone by Arizona receiver Larry Fitzgerald, giving the Cardinals a 24-13 lead, and he forced the referees to litter the field with penalty markers.
Finnegan was flagged twice for unnecessary roughness, totaling 28 yards, and was flagged a third time for illegal contact, but that five-yard penalty was declined.
The Rams knew what they were getting with Finnegan when they signed him in free agency a year ago. He's a playmaker, but his antics can cost the team with penalties.
The trade-off has been even up to this point, but is that still the case?
Finnegan has been considered a premier corner in recent years, but eventually his coverage skills will deteriorate. Is that happening to Finnegan, who turns 30 in five months?
Or, has the absence of Kurt Warner made us forget how unbelievably talented Fitzgerald is? Will Finnegan rebound against lesser receivers?
It's too early to tell, but if this keeps up, the Rams will be forced to start Trumaine Johnson.
We knew Jared Cook was heavily underutilized during his tenure in Tennessee, but does he have the ability to be an elite tight end in the NFL?
Cook was by far St. Louis' most potent weapon on offense against Arizona. The 6'5" tight end hauled in seven passes for 141 yards and two touchdowns.
Cook had an early hiccup in the game after catching a 47-yard would-be touchdown that he fumbled at the 1-yard line. Had it not been for that avoidable error, it would have been a three-touchdown performance for Cook.
Obviously, we can't answer those questions with only one game to reference.
Then again, Tony Gonzalez (three catches, 36 yards) and Graham (four catches, 45 yards) didn't come close to Cook's production in their showdown, while Gronkowski was inactive for his Week 1 game.
If this production continues, the Rams may have found the biggest steal in free agency.
St. Louis running backs had 21 total carries in the game, and second-year player Daryl Richardson took 20 of those carries.
Richardson has great speed and is explosive through gaps, so he has value to the offense, but at 206 pounds, he's not built as an every-down runner.
Richardson ran the ball 10 times in each half. The first half, he averaged a respectable 4.0 yards per carry, but in the second half, his averaged dropped to 2.8 yards per carry.
If the Rams wish to benefit fully from Richardson's play, he needs to be used sparingly throughout the game rather than carrying the entire workload.
Isaiah Pead, who was out of action against Arizona due to a one-game suspension, will return to the lineup for St. Louis' Week 2 game at Atlanta.
Pead's presence will help the Rams formulate a more well-balanced approach in the run game.
Steven Gerwel is the longest-tenured Rams Featured Columnist at Bleacher Report and serves as the Rams game-day correspondent. You can find more of Gerwel's work by visiting his writer's profile or by following him on Twitter.