KANSAS CITY, Mo. (AP) — The Kansas City Chiefs surprised just about everyone with their season-opening win in New England, especially the reigning Super Bowl champs, who had their festive night celebrating another Lombardi Trophy spoiled by Alex Smith and Co.

Most surprising, though, was how the Chiefs sprung the upset.

The defending AFC West champions were expected to keep games close this season with their ferocious defense, led by pass rusher Justin Houston and Dee Ford. But it was an offense with Smith under center and youngsters such as Tyreek Hill and rooking running back Kareem Hunt that managed to out-duel Tom Brady and his star-studded supporting cast in a 42-27 victory in Foxborough.

“You want to be multidimensional, right?” said Smith, who threw for 368 yards and four touchdowns in arguably his best game with the Chiefs. “You want to be able to spread the ball vertically. You want to be able to run, pass and spread it out horizontally as well. You want to be able to be good at all these different things. Inside the tackles, outside the tackles, all those things.

“You want to be well-rounded,” he said. “I think that makes you tough to defend.”

The Chiefs were certainly well-rounded. And they were a nightmare to defend.

Smith became just the second quarterback to throw for at least 300 yards with four touchdowns and no interceptions in the nearly two decades that Bill Belichick has been the Patriots’ coach. And it was the first 300-yard passing game by Smith in nearly two years.

Hunt, just the sixth running back to start an opener in franchise history, ran for 148 yards and a touchdown and caught five passes for 98 yards and two more scores. The third-round pick’s 246 yards from scrimmage were the most by a player in his first game in NFL history.

Hill had seven catches for 133 yards, including a 75-yard touchdown catch, in his first game as the Chiefs’ No. 1 wide receiver. His TD catch gave him five consecutive regular-season games with a play of 60 or more yards, the first player in NFL history to accomplish that feat.

Put that trio offensive together and it’s the first time since 2009 that the Chiefs have had a 300-yard passer, a 100-yard rusher and a 100-yard receiver in the same game.

“It was a huge game for us. We wanted to start off on the right foot,” Hunt said. “The whole team played great, especially the offensive line. Those guys were making holes all night. I was able to find creases, and run hard behind those guys, especially after I started slow.”

For all the positives, it was still an imperfect performance.

Hunt fumbled on the Chiefs’ first offensive play, something he only did once during his entire college career at Toledo. They had an unsightly 15 penalties for 139 yards. And their defense failed to force a turnover of its own, though they did make a couple of key stops on fourth down.

The biggest downside, though, was the torn Achilles’ tendon safety Eric Berry sustained in the fourth quarter. Berry was playing his first game since signing a $78 million, six-year deal, and had been having a standout game not only stopping the run by holding Rob Gronkowski in check.

“He will be out,” Reid confirmed Friday. “Eric won’t be playing.”

At least the Chiefs have some time to consider their options. Their victory on Thursday night means they have a few extra days to get ready for their home opener against Philadelphia on Sept. 17.

And while the Chiefs intend to spend time enjoying a tone-setting win over the Patriots, Smith made it clear that attention will swing swiftly to the next game on the schedule.

“Just because you do it one night doesn’t mean it will just carry over,” he said. “You have to find a way to beat the next opponent and the unique challenge they present.”

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