The first week of the NFL season, like Tom Brady’s birth certificate, only serves to deceive. One game is a small sample, of course, and it also comes at the point of the season that reveals the least. Teams generally improve more from Week 1 to Week 2 than at any other point of the season. The opening week can provide clues, but just as often it provides a fleeting, incomplete impression.

The NFL season can change in an instant, further proof of which came Sunday. In the span of a head-spinning half-hour, Vikings kicker Greg Joseph shanked a 37-yarder that transferred a victory from Minnesota to the Arizona Cardinals; Mike McCarthy’s brain lock nearly negated Dak Prescott’s last-minute heroics for the Dallas Cowboys; and the Tennessee Titans completed an out-of-nowhere comeback in overtime in Seattle. It was thrilling and maddening and breathtaking, the emotional concoction the NFL, for all of its ills, can deliver so consistently.

Two weeks are a bad amount of football from which to draw conclusions, other than that one week is even worse. Jameis Winston may not be an MVP candidate — the Saints didn’t score until the fourth quarter. Russell Wilson may not be untouchable with new offensive coordinator Shane Waldron — the Seahawks scored six points after halftime, blew a 30-16 fourth-quarter lead to the Titans, went backward on their only drive in overtime and avoided a game-ending safety only by virtue of a favorable call.

What can be drawn from the first two weeks, then? The West divisions are where it’s at — teams from the West are 13-3, including the 2-0 49ers, Rams, Cardinals, Raiders and Broncos. No. 2 pick Zach Wilson needs more time — Bill Belichick eats rookie quarterbacks for breakfast, but the New York Jets passer threw four interceptions and heard his coach say he needs to play more “boring.”

Brady threw five touchdown passes in yet another win, and the Jaguars suffered a 17th straight loss. Here is what to know.

The Cowboys won despite their endgame management. Greg Zuerlein bailed out McCarthy’s bizarre late-game strategy, blasting a 56-yard field goal as time expired after McCarthy decided against using available clock to advance the ball into better position. Amid a flurry of nail-biting finishes — hug a Vikings fan — the Cowboys nearly missed a chance to knock off the Los Angeles Chargers.

Even more significant than Dallas’s 20-17 victory, perhaps, was the emergence of the Cowboys’ defense. Justin Herbert looked like one of the best quarterbacks in the league last week at Washington, but Dallas’s young, speedy defense contained him. Herbert had 338 passing yards, but the Cowboys held the Chargers to one touchdown and twice picked him off, once in their own end zone.

Second-year cornerback Trevon Diggs, one of the fastest players in the league, had a crucial early interception, rookie linebacker Micah Parsons filled in at edge rusher in relief of injured star DeMarcus Lawrence, and linebacker Leighton Vander Esch made two tackles for losses. The Cowboys showed they have enough defense, and the right kind of defensive playmakers, to be considered an NFC East favorite.

In defiance of all reason, the Ravens finally beat the Chiefs. Here are some reasons the Ravens should not have won Sunday night: They have 15 players on injured reserve, not even including Ronnie Stanley, who didn’t play; Lamar Jackson threw a pick-six on the opening possession; they had never beaten Patrick Mahomes; they trailed by 11 in the third quarter.

And yet, the Ravens shook off a gut-punch loss from last Monday night in Las Vegas and topped the two-time defending AFC champions, 36-35, behind 251 rushing yards, 107 of them from Jackson. Whether the Ravens can withstand their injuries for a whole season remains to be seen. What’s certain is that nobody can doubt Baltimore’s fight or Jackson’s brilliance.

Injuries dominated the day. Four starting quarterbacks — Andy Dalton, Carson Wentz, Tyrod Taylor and Tua Tagovailoa — finished games on the bench. In Pittsburgh, star pass rusher T.J. Watt never returned after suffering a groin injury in the second quarter. Baker Mayfield and Derek Carr limped off, but they didn’t miss any snaps. Browns wide receiver Jarvis Landry missed most of the game. Defensive end Brandon Graham, still a productive player at 33 and the heart and soul of the Philadelphia Eagles, tore his Achilles’ tendon and said he will miss the season.

The injuries will ripple in many directions, none with more consequence than Dalton’s. It could force Coach Matt Nagy to lift the curtain on the Justin Fields era before he planned. In relief Sunday during Chicago’s 20-17 victory, the rookie quarterback was shaky. Fields finished 6 for 13 for 60 yards. A Bears interception deep in Bengals territory gave Fields a chance to seal the win in the fourth quarter. But the Bears had to settle for a field goal, and on their next possession, Fields threw an interception that briefly jeopardized the win.

Houston Coach David Culley didn’t know yet whether Taylor could play next week. If Taylor can’t recover by Thursday night, when the Texans host the Panthers, rookie Davis Mills would be the starter, seemingly helping Carolina’s chances of starting 3-0. Coach Brian Flores was hopeful Tagovailoa can return by next Sunday, and the Dolphins will need everything they can get against the undefeated Raiders.

The Dolphins lived a nightmare. Less than five minutes into the Dolphins’ AFC East showdown against the Bills, a chance for revenge after Buffalo knocked them out of the playoff picture last year, Tagovailoa hobbled off the field with a rib injury, the result of a crushing A.J. Epenesa hit, and rode a cart to the locker room.

Behind backup Jacoby Brissett, the Dolphins fell behind 14-0 midway through the first quarter and lost, 35-0. The Bills’ passing offense needed a boost after its Week 1 flop against the Steelers, and it met the right opponent. The Bills have scored 91 points against the Dolphins in their past two meetings, and Flores is 0-5 in his career against the Bills.

Cooper Kupp might be a top-five wide receiver. Among the most overlooked aspects of Matthew Stafford’s arrival in Los Angeles has been perhaps the most impactful through two games with the Rams: Stafford has unlocked Kupp, whose combination of sudden speed and rugged after-the-catch running makes him one of the elite wideouts in the NFL.

In the Rams’ 27-24 victory in Indianapolis, Kupp caught nine balls for 163 yards and two touchdowns. He emerged as Stafford’s unquestioned favorite target. When the Rams fell behind 21-17 early in the fourth quarter after a bizarre miscue in which the snap bounced off the up man in Los Angeles’s punt formation, Stafford hit Kupp on consecutive passes that covered 54 yards. The Rams wouldn’t trail again.

Kupp caught seven passes for 108 yards and a touchdown in Week 1. In his fifth season, he’s staking his claim as one of the best wideouts in the NFL.

Jon Gruden can finally be happy with Derek Carr. True to his nature, Gruden has had a wandering eye for quarterbacks since he took over as head coach of the Raiders. Two weeks into his fourth season, Gruden may finally love the one he’s with. The Raiders are 2-0, and Carr has produced like an MVP candidate.

Carr has some of the best traditional stats of any passer in the league — 817 yards, four touchdown passes and just one interception. He led the Raiders to a 14-point comeback last week vs. Baltimore. Against the Steelers, he took on one of the best pass rushes in football and didn’t blink.

Carr has been a master against the blitz. In Week 1, he thrived against constant pressure from the Ravens. With the Raiders up 16-14 early in the fourth quarter Sunday, the Steelers sent six rushers at him on third and 10. Carr calmly backpedaled and heaved a pass that traveled 57 yards in the air, a teardrop that landed in speedster Henry Ruggs III’s hands for a 61-yard touchdown. The Raiders have a hard task in the AFC West, but they may have a quarterback who gives them a chance.

Culley made the strangest decision of the season. In the second quarter of the Texans’ 31-21 loss to the Browns, Culley declined an offside penalty called at the snap before a 13-yard gain on third down. Culley effectively traded third and 10 for fourth and two at midfield. It seemed like a reasonable and interesting choice — Culley seemed to believe he had a better chance to convert from two yards on one down than 10 yards on two.

And then Culley sent out his punter. He had declined a penalty so he could punt.

“We felt like, at that point, we could have a chance to get better field position by holding them,” Culley said. “We didn’t make it.”

On the other sideline, cameras showed, Browns Coach Kevin Stefanski mouthed, “What?” He spoke for everyone. The Texans have been a pleasant surprise; they gave the Browns a scare before Taylor suffered an injury. Decisions like Culley’s aren’t going to help.

“Looking at it again, I’d just have to look at the situation and see what I would do the next time,” Culley said.

It’s hard being an NFL coach. One of the easier parts is not punting until you have to. It certainly shouldn’t be a lesson you learn on the job.