I'm growing a little tired of all the Roman numerals.
Players of the Game
Aaron Rodgers was truly the game's MVP, leading all players with a 0.19 Win Probability Added (WPA). His 304 yards, 6.9 net YPA, and 3 TDs were good enough to produce 10.5 Expected Points Added (EPA) and ultimately a 6-point margin.
Strangely, despite Ben Roethlisberger's two interceptions and failed final drive, he actually produced 11.6 EPA, slightly more than Rodgers did. This means, in terms of moving the ball and getting first downs, Roethlisberger played just as well as Rodgers. It's just that the way the game unfolded, BR was holding the bag at the end of the game. Rodgers' Success Rate was very low at 38.1%, while BR's was 47.8%, right where his season average was.
Had it not been for the Mendenhall fumble, costing -0.18 WPA, things may have unfolded very differently. As expected, the running game (aside from the fumble) for both teams was inconsequential. James Starks totaled -0.4 EPA but cost a net of -0.10 WPA. Mendenhall carried the Steelers for a TD drive, but his lost fumble more than washed it out, netting him -0.11 WPA.
Despite his drops, Jordy Nelson's 9 catches for 140 yards topped all receivers with 0.16 WPA and 6.4 EPA, making him a legitimate contender for MVP. Over 60% of Rodgers' EPA and 80% of his WPA came in passes to Nelson. It's very hard for a WR to do much better.
The tight ends were not a factor.
Linebacker Desmond Bishop was the defensive MVP of the game. Much of his game-leading 0.35 +WPA and 8.8 +EPA came from his fumble recovery, but nearly as much came from other less notable plays. Bishop led all front-seven defenders with 6 tackles plus 2 assists, including 3 tackles for losses, good for a 1.40 Tackle Factor (TF). Nick Collins was next, by virtue of his pick-six in the first quarter. Clay Matthews was third in +WPA mostly thanks to forcing the Mendenhall fumble.
Plays of the Game
The Matthews-forcedBishop-recovered Mendenhall fumble mentioned above was worth 0.18 WPA. Just as big was the 3rd and 10 31-yd pass to Greg Jennings with 5:59 to play, also worth 0.18 WPA. The leverage was huge there. A punt gives PIT all kinds of time and options to either play for the tie or the win. The successful conversion helped put GB up by 6, putting immense pressure on PIT on their final possession.
Next was the Collins pick-six, worth 0.17 WPA. Roethlisberger's 25-yd TD pass to Mike Wallace on 3rd and 3 was also big, worth 0.14 WPA. Jordy Nelson had the next two biggest plays. His 38-yd reception to the PIT-2 was worth 0.13 WPA, and his 29-yd TD catch in the first quarter was worth 0.11 WP.
Should the Packers have gone for it on 4th and goal from the 5 on their final drive of the game?
They opted for the easy FG to go up by 6. The Steelers would now need a touchdown, but often, forcing a team to go for the win rather than the tie can be counter-productive. This might be a little abstract, but by channeling your opponent into a more aggressive, and likely more optimal risk/reward posture, might not be smart. In other word, even if GB fails on the 4th down TD attempt, the Steelers are left at or inside their 5 yd-line and are "thinking FG."
From the 5, conversions are successful 37% of the time. A successful conversion puts GB up by 10 points, sealing the win with a 1.00 WP. A failed conversion gives PIT the ball at their own 5 with 2:10 to play, worth 0.87 WP to GB. On net, the go-for-it option is worth a 0.92 WP.
FGs from the 5 are good 97% of the time. Going up by 6 and kicking off is with worth 0.75 WP. A missed FG puts the ball on the 20, worth 0.83 WP. On net the FG option is worth 0.75 WP.
WAIT! Did I just say that missing the FG would be better than making it? Yes, that's exactly what I said, and historically, that's exactly the case. The reason is likely because teams down by 3 play for the FG in that situation, while teams down by 6 are forced to play for the win. Once inside FG range, they pull up and stop taking risks, accepting a long FG attempt that, even if successful, only buys them a tie--0.50 WP. I suspect Tomlin would be thinking differently, so the answer to whether the Packers should have gone for it isn't so clear. But based on league-baseline numbers, and some counter-intuitive thinking, going for it would have been the better decision by large margin, about 0.15 WP.
The only thing crazier than going for the TD in that situation would have been attempting an onside kick after the FG.
If the Steelers were unprepared for it (and that's a big if), the onside attempt would have been worth +0.09 WP more than the deep kick.
Up by 6 points, an successful onside kick seals the game. A failed attempt still requires PIT to score a TD and leaves GB with a 0.67 WP. When onside kicks are surprises, they are recovered 60% of the time. This makes the net value of the onside kick 0.86 WP. Kicking deep typically gives PIT the ball at their own 27, worth 0.75 for GB.
I doubt it would have been a surprise, given that Tomlin did the virtually same thing to McCarthy in last year's match-up between the two teams, making the deep kick almost certainly the right call.
Congratulations to the Packers and their fans. Again, we were treated to another great Super Bowl that came down to the final drive.