Though a potent running game has drawn praise, Drew Brees plays a big role in the Saints’ success. (AP Photo/Gerald Herbert)

The four division leaders in the NFC stand at nine wins or better after Week 13. Each looks like a near lock to come away with their division in four weeks’ time, but home field advantage is still up for grabs.

That leaves for a good deal of healthy debate over which of the four — the Eagles, Saints, Rams and Vikings — is actually the class of the NFC at the moment. Diving deep into the PFF grades and advanced stats for each, let’s go through the position groups to find a true favorite.

Quarterback – Saints

If the hype surrounding Carson Wentz this season hadn’t gotten so out of hand as the Eagles sat atop the NFC East, there would be little argument here. Drew Brees is still firmly in the elite class of NFL quarterbacks. He bests Wentz in almost every conceivable statistic, except touchdown passes. Sunday night’s game against the Seahawks showed firmly that Wentz’s accuracy can still be a major issue. Brees leads the league in adjusted completion percentage at 80.2 while Wentz’s 70.4 figure is only good enough for 25th among starters. Brees also gets the nod in PFF’s grading system, albeit barely (85.8 vs. 85.7). While Case Keenum has been incredible at avoiding sacks – his 6.2 percent sack conversion rate is among the best we’ve ever seen – and Jared Goff has taken a massive step forward in Year 2, both are a comfortable notch below in PFF grading.

Weapons – Rams

If this was purely wide receivers, the Vikings’ Adam Thielen (86.5 overall grade) and Stefon Diggs (83.0) would take the cake. If it were solely running backs, the Saints’ Alvin Kamara (90.1) and Mark Ingram (75.7) would run away with it. At tight end, Zach Ertz (80.5) has been easily the most dynamic of the four teams. When looking at all three positions in totality though, the Rams have the fewest holes, legitimately sending five dynamic weapons onto the field every single play.

The additions of Sammy Watkins (78.4), Cooper Kupp (78.1) and Robert Woods (80.3) give Los Angeles three receivers grading out among the top 32 – the only such team in the NFL that can boast that. Add to that the resurgent Todd Gurley out of the backfield and the Rams take this one.

Offensive Line – Saints

With a healthy Jason Peters, the Eagles might have the best offensive line in the NFL. The difference between Peters and his replacement (Halapoulivaati Vaitai), though, has been night and day. Big V has already allowed 12 combined sacks and hits on Wentz. The Saints’ offensive line on the other hand boasts the second-best pass-blocking efficiency in the NFL and has paved the way for the league’s most efficient rushing offense.

Front Seven – Eagles

This one is a fun debate. The Rams boast the highest-graded defensive tackle in Aaron Donald (97.5) while the Saints employ the NFL’s second-highest-graded edge rusher in Cameron Jordan (93.5), but the rest of their units have been lackluster. The Eagles and Vikings are much more well-rounded. It’s tough to beat the dominance of the Eagles’ front four, however. They are the league’s highest-graded defensive line by pass-rushing grade, and third-highest by run defense. They have a six-man rotation with every player grading at 77.0 or above. Brandon Graham and Vinny Curry are first and third among all edge defenders in run-stop percentage. Behind them, Nigel Bradham and Mychal Kendricks have both graded out at least above average on the season.

Secondary – Vikings

After the most debatable positional group in the front seven defenders, this one is the least up for debate. Harrison Smith is the league’s highest-graded safety and is allowing a passer rating of only 23.0 on his 33 targets. Xavier Rhodes and Terence Newman are the only starting duo among the four division leaders to both be allowing 1.0 yards per coverage snap or fewer on the season. The only other claim could come from New Orleans and the fact that Marshon Lattimore is far and away the highest-graded cornerback on these four teams, but there are far too many holes in the rest of the unit to argue.

Verdict – Saints

As winners in two of the five categories, the Saints come away as the victors. Maybe more importantly though, is that if each category was ranked from top to bottom, the Saints would only come away in last place for their front seven. Their weapons and secondary would likely both be ranked second at full strength. That’s a scary proposition for the rest of the NFC, especially if they have to travel to the Superdome come playoff time.

Mike Renner is a writer for Pro Football Focus and a contributor to The Washington Post’s NFL coverage.

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