The Mets spoke of belief, of hope, of perseverance, of resilience. A silent Citi Field spoke the truth.

Counting on their ace in one of the year’s most crucial moments, 38,389 fans watched Jacob deGrom cruise through Thursday night’s start against the Cubs then suffer his first loss in two months, as the Mets dropped their season-worst sixth straight home game, 4-1, and fell five games behind Chicago for the National League’s second wild-card spot.

After allowing just one home run in his previous eight starts, deGrom served up a pair of shots to Victor Caratini — including a tie-breaking, three-run bomb in the seventh inning — handing the Mets back-to-back sweeps in Queens for the first time in nearly 15 months.

DeGrom’s streak of 17 straight starts allowing three or fewer earned runs came to an end, striking a blow to his bid for back-to-back Cy Young Awards. The Mets’ postseason hopes took a bigger hit.

“It’s tough. The last six games, that’s tough to swallow,” manager Mickey Callaway said. “The hardest part is you’re six games closer to the end. … Things have snowballed. Six in a row, that’s a big snowball.”

DeGrom (8-8) received unusual support early, as J.D. Davis crushed a two-out, first-inning solo shot off Jon Lester over the apple in center field for his 18th homer of the year. But the Cubs quickly struck back in the second, with Caratini’s solo homer to right breaking deGrom’s 21-inning streak without allowing a home run.

DeGrom followed with dominance, retiring the next 15 hitters he faced. Then came the knockout punch no one saw coming.

“You’re like, ‘What just happened?’ ” Callaway said of deGrom surrendering multiple home runs for the first time since June 18. “He was dealing. That’s the thing, guys are on a roll until they’re not on a roll. That’s how this game goes.”

After allowing a pair of soft, one-out singles in the seventh inning, deGrom threw Caratini an up-and-in slider, the same pitch that previously landed in the upper deck in right field. The sequel traveled further and faster. Before Thursday, Caratini had hit just seven home runs all season.

DeGrom was pulled after seven innings — having allowed four runs and five hits, while striking out seven and walking none, throwing 100 pitches (71 strikes).

“That one stings. I felt like I had really good stuff,” deGrom said. “It’s definitely frustrating.”

As usual, deGrom didn’t get much help from his lineup. In each of the first three innings, the Mets left a pair of runners on base. They went hitless in 13 straight at-bats with a runner in scoring position. In the final six innings, the Mets produced just one hit.

“It’s real frustrating. We want to go out there and do what they did to us basically. We want to sweep them and get in that last wild-card spot,” Jeff McNeil said. “There’s still hope. We’re five games out.”

It was just a half-game three weeks ago, as the Mets wrapped up an incredible 15-1 stretch. Now, another similar, unlikely, improbable run might be the only route back to the playoffs.

“We know we have to win every game that we can. We gotta win a lot. There’s definitely pressure there,” McNeil said. “We controlled playing against the Cubs this week, and we didn’t do what we were supposed to. We’re gonna need some help now.”

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