There are plenty of places to start when recapping the head coaching era of Tom Coughlin with the New York Giants.

There’s obviously the two Super Bowls, there’s the disappointing last act that inevitably led to his “stepping down,” but perhaps the most natural place to start is the beginning.

Coughlin came over to the Giants in 2004 at the age of 58, following a year out of the game after an eight-year stretch with the Jacksonville Jaguars. Coughlin’s time in Jacksonville granted him one of the more impressive resumes for a potential head coach. As the first coach for the expansion Jaguars, Coughlin took the team to the playoffs in its second year of existence in 1996 and would take the team back the following three seasons, reaching the AFC Championship Game in two of those four years.

Like with Jacksonville, the Giants saw success in their second year under the coach. Jumping from 6-10 in 2004 to 11-5 in 2005. The Giants wouldn’t have a losing record again until 2013.

Of course, anyone could list the final records of those seasons and base Coughlin’s performance on how often the Giants won under his supervision. But that’s not why you’re here.

By The Numbers

Here at numberFire we have two main metrics to place some context around what happens on the football field. The first is Net Expected Points (NEP) metric is more tailored for the specific on-field play by measuring the value of each play on the field based on how an average team would be expected to perform in each scenario using historical data.

There were some ups and downs during the Coughlin era in New York, but even without factoring in the two Super Bowls, much of what Coughlin brought was above average football, especially through 2012. Below is a chart showing the rankings of the Giants during Coughlin’s tenure in nERD and Adjusted NEP per play for offense and defense. The adjustment for both efficiency stats are for the opponents faced.

From that chart and without any prior knowledge, the two Super Bowl winning squads are hard to find. The Giants ranked among the top 10 in nERD in three seasons under Coughlin, but none of those three ended the season as Super Bowl champion.

The only truly great team during a regular season was the 2008 squad, which followed the 2007 title winners. Those Giants were fourth in nERD -- but even more impressively were second in the league by Adjusted NEP per play on offense. While that was greatly aided by two 1,000-yard rushers in Brandon Jacobs and Ahmad Bradshaw, they also ranked fifth in passing by Adjusted NEP per play while the leading receiver on the team was Domenik Hixon.

What Went Wrong?

Having only one great regular season is not a knock on Coughlin, especially when two Super Bowl runs were put in between.

Really up until the 2013 season, the Giants had been an above average team even though Coughlin’s job had been called for on more than one occasion during that stretch. Keeping a team above average for that amount of time is not an easy feat. Look at a coach like Jeff Fisher, who has seemingly permanent job security by keeping his teams barely average for an extended period.

That 2013 season is the one that saw Eli Manning bottom out and lead the league with 27 interceptions. While the offense was a mess, the defense was still good enough to rank eighth by Adjusted NEP per play. The past two seasons saw the opposite issue. While Ben McAdoo was hired to turn the offense around -- and he did, Manning had his best season by Passing NEP per drop back in 2015 -- the defense, which was once the calling card for these teams, ranked 25th in Adjusted NEP per play two seasons in a row.

Two seasons of 6-10 is never good for a head coach, but this past year didn’t quite feel like 6-10 for most Giants fans, and that was due to the all of the close losses and near wins. In a way, that made it easier to deal with. In a way it made it much worse.

In five of the the Giants’ 10 losses in 2015, the team had at least a 90 percent win probability at one point of the game, per the metrics at numberFire Live. Move that mark down to 85 percent and the Week 17 loss to the Philadelphia Eagles comes into play, making it more than half of the team’s losses.

And that’s where things went wrong for Coughlin and why the need to part ways was finally realized.

Coughlin’s late-game decisions had cost the Giants more than a few times during this run, whether it be time management by holding on to timeouts, play calling or other fourth down decisions. Game management is only one aspect of coaching, but with an average team repeatedly playing close games, it’s one part that is going to show up often, and it’s where Coughlin struggled the most during his time on the sideline.

What It All Means

There’s also an unquantifiable “leader of men” aspect needed for a head coach in the NFL, one that Coughlin very clearly had. It’s needed, to some extent, to bring the 11th best team in the league to win a Super Bowl -- twice.

It was also made clear by the outpouring of respect from former players and many others around the league soon after the announcement was made that Coughlin would be stepping down.

The Giants now need to fill a position that hasn’t been vacant over the past 12 seasons. There’s been rumors of New Orleans Saints head coach Sean Payton, and both current coordinators have been expected to get interviews.

It’s unknown how the Giants will attack this search because it’s been so long since they’ve needed to make this kind of hire. Only Bill Belichick and Marvin Lewis were hired before Coughlin and are still with that same team.

A key point in Coughlin’s announcement was the lack of the word “retirement,” leaving the door open for another gig.

Whether he coaches again or not, Coughlin will go down as one of the best coaches in Giants history. Whoever comes in to replace Coughlin might be an instant upgrade on the current version of Coughlin as a coach but will have giant shoes to fill to match the sustained success he brought during his 12 seasons in blue.