Even the savviest NFL prognosticators are bound to be caught off guard by some early-season developments. With one quarter of the season complete, several popular projections have come to fruition: the Patriots and Chiefs are the class of the AFC while the Dolphins, Redskins, Bengals and Jets are among the hapless outfits still in search of their first win. But whether it be by way of game-changing injuries or merely unexpected performances, the league has underwent some unforeseen shifts in September. With that in mind, we asked NFL reporters and editors from around the USA TODAY Network: what's the biggest surprise of the 2019 season so far? Jimmy Garoppolo’s struggles in the preseason, which followed his less-than-impressive performances last year before he got hurt, did not give me a whole lot of confidence that the 49ers could turn things around this season. And yet, here they are, top of the NFC West. (Granted, they got there on a bye weekend, but after consecutive seasons below .500, baby steps.) San Francisco has not played particularly well – those turnovers! -- and its opponents have been middle-of-the-pack teams. But wins are still wins, and they help a young team build confidence. The defense has been impressive so far and, if that continues, it will give Garoppolo the room he needs to progress and grow. The Carolina Panthers have survived without Cam Newton. With a battered Superman at quarterback, the Panthers went 0-2 as back-to-back home losses were laced with Kryptonite. With healthy second-year pro Kyle Allen taking the snaps, Carolina put up back-to-back road wins just when it appeared their season could spin out beyond repair. Go figure. It’s not like Allen is the next Patrick Mahomes – his five fumbles over two weeks have tested nerves – but he has shown some upside. He’s completed over 70% of his passes, hasn’t thrown a pick, fired 4 TDs in his homecoming game at Arizona and made J.J. Watt whiff on a should’ve-been sack with a deft duck-and-escape move. Yet much like their NFC South rivals in New Orleans, Ron Rivera’s team has taken some of the pressure off the quarterback by stepping up in other areas. The special teams have already blocked three punts and, led by Mario Addison, the defense collected 14 sacks in the wins. Guess that new 3-4 scheme was a good idea. Problem is, there’s a slew of injuries that resulted in 14 players listed on the injury report this week in addition to stud D-tackle Kawann Short going on season-ending IR with a torn rotator cuff. And the injury bug is severe on the O-line, which hastens the concern for leaky protection. It’s unclear when Newton will return with his weekly fashion statement costumes and the dynamic, multi-dimensional skill set that makes him so special. Yet it’s a shame that the franchise quarterback is on the shelf in the first place with an injury that occurred on an ill-advised scramble in his lone preseason game, when he needed to protect himself for the real games. In any event, at least to this point, Allen has been capable of running Norv Turner’s offense and Carolina looks able to stay competitive until Superman returns. Just hide the Kryptonite. Biggest surprise … hmmm. Gardner Minshew? Kyle Allen? Antonio Brown bounced out of the league after exiting his third team in six months and being relegated to homework? As is typically the case, the NFL is chock-full of surprises. But for my money, the craziest revelation has to be the Detroit Lions, who figured to be a tough out on game days but – in my opinion – also appeared thoroughly outclassed by their NFC North brethren at the season’s outset. (And opening their campaign with a come-from-ahead tie in Arizona was hardly encouraging.) But these are no Ford Family Frauds. The Lions have been as tough as any club the past three weeks, upsetting the Chargers and Eagles before taking the undefeated Chiefs to the wire in a slugfest that could have gone either way – literally if that dubious 100-yard fumble return by Kansas City’s Bashaud Breeland had been disallowed. The Leos aren’t stellar in any particular area – frankly, the defense has been disappointing overall thus far – but they’re making a lot of clutch plays at key moments, something quarterback Matthew Stafford has done a fair amount of over the years without getting requisite credit. Detroit faces the Packers and Vikings on the other side of its Week 5 bye, so we’ll find out quickly if their hot start is miraculously legitimate or just another Motown mirage. I certainly didn’t expect Saints quarterback Drew Brees, Steelers quarterback Ben Roethlisberger and Jaguars quarterback Nick Foles to play a combined five games (and not even a full five, for that matter) in the first quarter of the 2019 NFL season. The thumb, elbow and clavicle injuries that plagued the respective Super Bowl champions delivered a stark reminder: Even with rules changes to better protect quarterbacks, the risk remains high. No matter that Brees has started at least 15 games for New Orleans every year since 2004, with Roethlisberger close behind starting at least 11 games each of the last 15 seasons before ending his 2019 season in September. Foles’ injury history is more extensive, but most recently he was the Eagles’ injury savior as he led the Carson Wentz-less squad to a championship. An impressive but less-surprising outgrowth of this surprise: the Saints’ 2-0 record so far without Brees. Kudos to Teddy Bridgewater for quarterbacking wins over the Seahawks and Cowboys, and to a talented Saints roster on both sides of the ball for powering them. There have been a lot of unexpected developments this season. The injuries to Ben Roethlisberger, Drew Brees, Cam Newton and Nick Foles. The retirement of Andrew Luck. The Antonio Brown crash-and-burn. The poor play of Kirk Cousins. The holdouts and player power moves. But I think my biggest surprise has been Gardner Minshew. I didn’t for a second expect that this sixth-round draft pick would step in for Foles and give the Jaguars a chance to remain competitive. I figured his decent play in the second half of the season opener was kind of beginner’s luck, or the result of the opponent not being able to game plan for him. I figured that eventually, this eccentric kid would fall flat the following week once the pressure was on. But Minshew is actually good. He has seven touchdown passes and only one interception and has completed 69.4% of his passes. He’s aggressive. He’s fearless. He’s a baller. And for that, he’s my biggest surprise of the season. It's hard to pin down the biggest surprises of the NFL season, in part because the answer always will be linked to expectations that can vary from person to person. But it's not hyperbole to note that not one person would have projected Buccaneers outside linebacker Shaquil Barrett as the front-runner for defensive player of the year through the season's first four weeks. As a backup with the Broncos, Barrett was always efficient in a limited role. But his free agent options consisted of just two offers — from Tampa Bay and Cincinnati — and his one-year, $4 million contract is reflective of a player viewed as little more than a flier. Yet in addition to pacing the league with nine sacks, he's also recorded three forced fumbles and an interception en route to earning NFC defensive player of the month for September. It's natural to write off this performance as an aberration given the undrafted free agent's humble beginnings — he transferred to Colorado State from Division II Nebraska-Omaha when the school dropped its football program. But Barrett's performance hasn't been a mere matter of luck and timing, as he also leads the NFL in pressures with 28 and has routinely beat opposing linemen with superior pass-rush savvy. Even if his pace slows in October, he has positioned himself as a disruptive force worthy of a much bigger payday next offseason. The Detroit Lions. After losing 10 games a year ago (by an average of 12 points, no less), the Lions have been competitive in every game they've played this season. They've beaten both the Chargers and Eagles -- who some prognosticators picked to reach the Super Bowl -- and gave the Chiefs a run for their money last week, too. Sure, the Lions haven't played another NFC North team yet, and they'll probably come crashing down to Earth at some point. But they've looked shockingly good through the first four weeks. To me, it has to be all about Minshew Mania. Talk about unexpected. That an unheralded, rookie sixth-round quarterback has been able to step in and keep the Jaguars season afloat even after starter Nick Foles went down in the opener with a broken clavicle is nothing short of a stunner. But of passers with at least 100 attempts, Minshew ranks fifth in the NFL (behind only Patrick Mahomes, Russell Wilson, Dak Prescott, and Lamar Jackson) in QB rating with a mark of 106.9. He has completed almost 70% of his throws and has a touchdown-to-interception ratio of 7:1. He has used his mobility to keep plays alive, and has been resourceful in the pocket, delivering accurate throws. We’re not quite to the point where you have to wonder if Minshew stays on as the starter; he needs to continue this standard of play for at least a few more weeks. And more importantly, he needs to keep putting Jacksonville in position to win. But the Jags are tied with everyone in the AFC South at 2-2, so the team could still make a run. Minshew Mania has been a fun surprise this year. Let’s see how long it lasts. The NFL’s Offensive Rookie of the Month for September was selected with the 178th overall pick in the sixth round due to league-wide concerns about everything from his arm strength to his height to his ability to succeed in an offense that wasn’t of Mike Leach’s design. So far, all he’s done is: • Replace Nick Foles in the first quarter of his first regular-season game and throw two touchdown passes against the Chiefs in that contest; • Lead the NFL in red-zone passer rating (123.9); • Have a 97.4 passer rating with three touchdowns and no interceptions under pressure; • Complete seven of 16 passes of 20 or more air yards for 246 yards, one touchdown, and no interceptions. Among rookie quarterbacks through their first four games in NFL history, only Cincinnati’s Greg Cook has a higher passer rating than Minshew’s 106.9, and Cook was thought by none other than Bill Walsh to be potentially the best quarterback of all time before a shoulder injury ruined his career. Cook was the fifth overall pick in the 1969 draft. That Minshew is accomplishing all of this with so little regard for his collegiate performances isn’t just the biggest surprise of the 2019 season so far – it’s one of the biggest shockers in recent NFL history. I am stunned by how many just plain awful teams there are in the NFL. For a league that prides itself on parity, the gulf between the haves of the league and the have-nots is wider than ever. Through four weeks of games, there are six winless teams, and just about all of them appear as if they would remain winless if they didn’t face each other during the season. But the Jets and the Dolphins, for example, have to play each other twice this season. So someone has to win by default. Unless, of course, they tie. Ugh. We have already seen two games where the point spread has been above 20 points, which would more resemble a college game between No. 1 Alabama and Patsy U. This weekend, New England is favored by 16.5 over Washington and the Eagles are favored by 15.5 over the Jets. So far, only Miami is in all-out tank mode. But what does that say about the other teams that are just plain awful? Remember the saying, “on any given Sunday?” For Miami and some others, that should be changed to “not any Sunday.” The complete domination of the New England defense through four games. Now, to be fair, they haven't exactly gone against any of the NFL's elite, or even good, offenses, but the way they have dismantled the Steelers, Dolphins, Jets and Bills has been rather remarkable in its brute efficiency. They have allowed just one touchdown all year, that on a fourth-down play at the goal line where Buffalo's Josh Allen barely got the ball across the plane of the end zone before it was swatted away. The Patriots rank first in total yards, first downs, third-down conversions and points, are tied for first in sacks, and are second in rushing yards and passing yards. Perhaps it's an unsustainable pace, but the Patriots have looked impenetrable, not to mention unbeatable. The league is still thriving with backup/young quarterbacks stepping in for iconic and Super Bowl quarterbacks. Ben Roethlisberger, Eli Manning, Drew Brees, Nick Foles and Cam Newton are all on the sideline replaced by Mason Rudolph, Daniel Jones, Teddy Bridgewater, Gardner Minshew and Kyle Allen. In years past, all these replacements would signal a dip in production, hype and hope. Somehow these teams are surviving. If you love talking football, we have the perfect spot for you. Join our Facebook Group, The Ruling Off the Field , to engage in friendly debate and conversation with fellow football fans and our NFL insiders .