PHOENIX — The Chase Field center field scoreboard often calls for “chaos,” and for two days the home team and the crowd obliged as the upstart Diamondbacks scrapped their way back into a surprise tie in the National League Championship Series via loud and late-game heroics. But Saturday night in the pivotal Game 5, Phillies ace (and former Met) Zack Wheeler plus the familiar October combo of Kyle Schwarber and Bryce Harper, calmed things down here considerably, returning a sense of normalcy and predictability to the proceedings.

Thanks mostly to Wheeler, one of the best big-game pitchers going, who Mets doctors recommended against signing (more on that later), the underdog Diamondbacks were also returned to an ultra-difficult spot following the 6-1 Phillies victory. They head to Philly’s unfriendly confines, Citizens Bank Park, down three to two in games and needing to sweep two against a team that is an October-best 28-11 in their home park.

The Phillies may also be baseball’s top performer in the free-agent market, and the $118 million, five-year deal three winters ago for Wheeler, which looked like an overpay back then, has turned out to be one of the best starting pitching signings ever, right up there with Greg Maddux, Mike Mussina and Max Scherzer (the Nats’ version of course).

But let’s be fair. You never know how these things are going to go. Taijuan Walker, another former Met, signed with the Phillies for $72 million over four years, and after a nice first half, he’s relegated to October mop-up duty.

Anyway, Wheeler was the best antidote for what temporarily ailed the Phillies, a shutdown starter a day after their bullpen was basically emptied and Phillies hitters were just slightly off their usual overwhelming game. Wheeler’s seven stellar innings were just what the doctor ordered as the sides prepared to return to Philly for more bedlam (the chaos here was darned good, but it’s tough to top that bedlam). The Diamondbacks do not scare and they are resilient as hell, but if they watched closely they saw a Philly team that appears close to being back on its all-around game.

Schwarber and Harper, two more outstanding free-agent signings by Philly, hit a pair of monster homers in the sixth inning off Diamondbacks ace Zac Gallen, and the Phillies have now outhomered their opponents 22-5 this October. Their only real weakness is timing. The last 15 long balls were solo shots.

Wheeler didn’t need much help, and though his $24.5 million salary is merely 59 percent of each of the Mets’ salaries of Justin Verlander and Scherzer, who are both still going for other playoff teams, I am not here to bash the Mets. When the Mets decided not to try hard to keep their own Zack Wheeler as a free agent three winters ago, I got it.

Wheeler owned an extremely ordinary 100 ERA-plus at that point. Mets doctors were among other medical people who raised red flags over his arm. The $118 million cost seemed steep (though at least the White Sox bid more and many other teams were right there). And of course, Steve Cohen was only known as an equity trader and art collector back then, so the Mets’ budget was somewhat less than limitless.

The Mets weren’t necessarily being crazy and cheap thinking Wheeler wasn’t a $100-million pitcher. The final figure did seem startling at the time, but give advanced analytics credit for this one. The numbers guys who saw the velocity that sometimes hit 100 mph and analytics clues suggested a lot more was in the tank.

Wheeler and the Phillies came together mostly because he wanted to be near New Jersey (his wife’s family lives there). Since Queens is somewhat close to New Jersey it stands to reason the Mets might have had a decent chance. But word is it was out of the Mets baseball people’s hands as his medical history — he’d had Tommy John surgery — caused Mets medical people to recommend against it.

These things are tough to predict, and as it turns out, Wheeler has proven to be one of the healthiest and sturdiest pitchers in the majors since moving 90 miles to the south. The Phillies have been right more than anyone when it comes to these big-ticket signings, and almost from the start Wheeler showed he had become nothing short of one of the best free-agent signings ever. In his three seasons in Philly, Wheeler is fourth in innings pitched with 629 ¹/₃ (behind Gerrit Cole, Sandy Alcantara and Aaron Nola), fourth in starters ERA at 3.08, fifth in WHIP at 1.06, ninth in opponent batting average at .224 and fifth in strikeout-to-walk ratio at a neat 5-to-1.

He has been even better in the postseason. His 0.70 October ERA is the all-time best for pitchers who faced at least 200 batters, just ahead of the great Mariano Rivera’s 0.72. So he’s topped the great Yankee, and showed the Mets while pitching the Phillies to within a game of the World Series.