Through Week 3 of the 2019 NFL season, a quarter of the teams in the league remain undefeated. The AFC East, NFC North and NFC West make up six of those eight teams, with the other two coming from the AFC West and NFC East. Three weeks does not make a championship team, however, so which of these undefeated teams look like contenders, and which might be pretenders as we look ahead?

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CLEAR CONTENDERS

Why fans should be hopeful:

The 42-year-old Tom Brady is the highest-graded quarterback in the NFL through three weeks, posting a 91.4 PFF grade to go along with seven touchdowns. His 2014 campaign was the last season where he finished the year with a PFF grade lower than 90.0 and even in his advancing years, we should expect the same in 2019.

New England also has our highest-graded linebacker in Jamie Collins (89.8) and the two highest-graded cornerbacks in Jonathan Jones (86.0) and Jason McCourty (84.3). Their defensive backfield is performing better than anyone else in the league, with the five players who have played 125 or more snaps all producing PFF grades of 78.0 or higher. They have allowed more touchdowns on offense and special teams (two) than on defense (0) and are a team built to have success in the passing game on both sides of the ball.

Why fans should be concerned

Injuries. They’ve lost left tackle Isaiah Wynn to the Injured Reserve, and right tackle Marcus Cannon missed their win over the Dolphins in Week 2. Injuries can derail any championship team, so keeping key players healthy will be important for the Patriots. There’s also the fact that they haven’t played a good team so far. The Pittsburgh Steelers looked bad even before the injury to Ben Roethlisberger, and they were heavy favorites over the New York Jets and Miami Dolphins. Still, they have made it look easy against those teams.

Why fans should be hopeful

They lost wide receiver Tyreek Hill to injury and the offense didn’t skip a beat. Quarterback Patrick Mahomes hasn’t been quite as good as his gaudy stats suggest, with some bad fumbles and dropped interceptions hurting his PFF grade, and he still ranks fourth among quarterbacks who have at least 50 passing attempts with an 83.2 PFF passing grade through three weeks. They have three wide receivers who rank in the top-20 in receiving yards on throws 20-plus yards downfield and will get Hill back at some point to make this offense even more electrifying.

Why fans should be concerned

Their secondary looks to be an issue once again. No Chiefs cornerback or safety on the roster has produced a PFF coverage grade of 70.0 or higher through three weeks. Charvarius Ward has allowed 186 receiving yards on throws into his coverage, the 14th-most among cornerbacks in the NFL so far this season. This was their undoing in the playoffs a year ago, and while their offense will keep them in contention, their season could have a frustratingly similar end in 2019 if they don’t improve on the back end.

Why fans should be hopeful

Dak Prescott is on his way to a career year with a PFF grade of 90.4 through three weeks. He has dominated on throws downfield, going 9-for-16 for 295 yards with five touchdowns and an interception. And as we wrote after Week 1, the addition of Kellen Moore as offensive coordinator has seen him go from strength to strength.

Three offensive linemen in La’el Collins, Tyron Smith and Zack Martin have all produced PFF grades of 79.7, with the three of them combining to allow just three total pressures through three games. The strength of their offensive line has shown in their run blocking too and was a big reason that both Ezekiel Elliott and Tony Pollard went for over 100 yards on Sunday.

Why fans should be concerned

There shouldn’t really be any concern for the Cowboys right now, but we’re going to learn a lot about how good they really are over the next four weeks. Games against the Saints, Packers and Eagles over the next month give them the opportunity to assert their dominance in the division and conference, setting themselves up for the postseason.

Why fans should be hopeful

While many were worried about a potential Super Bowl hangover for the Rams, that hasn’t been the case through three weeks. Wide receiver Cooper Kupp is off to a great start, ranking fifth among all receivers with at least 20 targets with an average of 2.58 yards per route run.

Aaron Donald has just one sack through three games, but he has still been dominant, registering 14 total pressures on 111 pass-rushing snaps. Four of his five solo tackles have resulted in a defensive stop, highlighting his work against the run, and it shouldn’t come as a shock when his sack numbers rise again in the coming weeks.

Why fans should be concerned

If there is a weak spot on the Rams offense right now, it’s the offensive line. Left tackle Andrew Whitworth is the highest-graded player on the line, but even he has a PFF grade of just 60.0 so far this season. That itself isn’t a bad grade, but it’s not what you’d be looking for from your best player on the offensive line. Through three weeks, the group has allowed 49 total pressures, something they’ll need to improve upon as the season goes on.

Why fans should be hopeful

The additions to the Packers' defense over the past two seasons are really starting to pay dividends. Edge defenders Preston Smith and Za’Darius Smith arrived via free agency this offseason and have made a big impact on the team’s pass-rush. Preston Smith has registered four sacks, two hits and nine hurries from 87 pass-rushing snaps, while Za’Darius has added three sacks, five hits and 13 hurries from 115.

Their first-round draft pick from a year ago, cornerback Jaire Alexander, is emerging as one of the better cornerbacks in the NFL this season, and his ability to find the ball is becoming one of the strengths of his game. He recorded six pass breakups across his 461 coverage snaps as a rookie in 2018, a total he has matched in just three games this season.

Why fans should be concerned

Aaron Rodgers is not a bad quarterback; let’s make that clear. That being said, we have seen a more conservative side to his game recently. In 2018, he shattered the PFF record for most throwaways in a single season (dating back to 2006) with 59. That was 19 more than the next highest-graded quarterback and we’ve seen more of the same this year. Through three weeks, he has thrown the ball away 11 times, putting him on pace to be right around that mark again in 2019. Throwaways aren’t necessarily a bad thing, but if it gets to a point this season where Rodgers needs to make things happen, can he flip the switch back to the dominant passer we saw in the past?

POTENTIAL PRETENDERS

Why fans should be hopeful

The Bills have one of the best safety duos in the NFL in Micah Hyde and Jordan Poyer with them ranking sixth and seventh, respectively, in terms of PFF defensive grade among safeties with 50 or more snaps through three weeks. Hyde was particularly impressive for them in their win against the Cincinnati Bengals this week, including forcing a fumble from Bengals wide receiver John Ross.

Why fans should be concerned

Of the 35 quarterbacks who have dropped back to pass 50 or more times this season, Josh Allen ranks 27th with a PFF grade of just 60.1. In isolation, there have been some impressive throws, but as we saw in his rookie season a year ago, the consistency hasn’t been there. Even when Allen has put the ball where it needs to be we’ve seen receivers drop the ball, with the eight drops on his throws tied for the second-most in the NFL through two weeks. The Bills face a huge test on Sunday against the New England Patriots and have the opportunity to stamp their claim as a threat to the Patriots in the AFC East. However, until they get more consistency on offense, it’s tough to put them into that bracket yet.

Why fans should be hopeful

After a shaky preseason and a ropey Week 1, quarterback Jimmy Garoppolo has rebounded with a pair of impressive performances against the Cincinnati Bengals and Pittsburgh Steelers. He has looked good throwing at the intermediate level of the field, particularly between 10 and 19 yards downfield where he has gone 7-for-11 for 119 yards with an interception and has posted solid numbers throwing the ball downfield. On throws 20-plus yards in the air, he has gone 6-for-9 for 193 yards and two touchdowns and an interception.

Defensively, they have been pretty solid across the board, with eight players who have played 80 or more snaps producing PFF defensive grades north of 70.0, with their top three cornerbacks in Richard Sherman, Ahkello Witherspoon and K’Waun Williams combining to allow just 276 yards combined in their coverage through three games.

Why fans should be concerned

They have yet to be tested by a good team and made hard work of the Steelers team that included a quarterback in Mason Rudolph who produced a PFF grade of just 32.9 in the game. A tough end of season stretch sees them take on the Seahawks twice along with games against the Green Bay Packers, Baltimore Ravens, New Orleans Saints, Atlanta Falcons and Los Angeles Rams.

Outside of tight end George Kittle, we’ve yet to see a receiver emerge, and their wide receivers alone have dropped five passes already this season. With that stretch to end the season looming large, the consistency of Garoppolo and the need for someone to establish themselves as the team’s number one receiver will be key if they hope to contend in the NFC West.

Why fans should be hopeful

Few people would have picked the Lions to win against the Chargers in Detroit or against the Eagles in Philadelphia, but they got the job done. Their skill position players have found success so far and provided quarterback Matthew Stafford with safe hands, combining to drop just four passes through three games. Stafford himself has been impressive when kept free from pressure, going 53-for-70 for 640 yards with six touchdowns and two interceptions. On the offensive line, second-year center Frank Ragnow looks right at home back in the middle of the line, leading all centers with an 84.2 PFF run-blocking grade so far this season.

Why fans should be concerned

The Lions will be disappointed with what they’ve gotten out of Trey Flowers so far. Dominant in New England, he has already matched his three missed tackles total in 2018, with three misses alone in the game against the Philadelphia Eagles. He has been solid as a pass-rusher so far, with a sack, two hits and eight hurries from 87 pass-rushing snaps, but the Lions would have been expecting more when they added him in free agency.

Stafford's success when kept free from pressure is great, but with their offensive tackle pairing of Taylor Decker and Rick Wagner combining to allow three sacks, three hits and 14 hurries in the opening three games of the year, there will be concern about keeping pressure away from him, with Stafford’s PFF grade dropping to just 48.8 when pressure gets to him.

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