At the end of spring training, Phillies officials cited several reasons to be bullish about Jake Arrieta.

For one thing, they noted that Arrieta was healthy again after pitching through knee pain for part of last season and having minor surgery in January. For another, they pointed to Arrieta’s arm angle, which was raised back to the high three-quarters slot that he used during his peak with the Cubs.

As always, though, the best proof is in the pitching. And Arrieta notched his fourth strong start in a row on Wednesday, holding down the Mets for eight innings in a 3-2 win, in the rubber match of a three-game series at Citizens Bank Park.

“It was one of the top two or three performances I’ve seen from Arrieta since he's been a Phillie,” manager Gabe Kapler said. “It was really impressive.”

Scott Kingery continued his scorching start with another home run. Cesar Hernandez also went deep for the Phillies, who got Rhys Hoskins back after missing a game with a sprained left ankle. But, they were without shortstop Jean Segura (left hamstring strain) and lost center fielder Odubel Herrera in the fifth inning with a cramp in his right hamstring. Neither injury is considered serious.

But this was all about Arrieta. Phillies starters threw a total of 19 innings in the previous four games, and with a four-game series starting Thursday night in the thin Colorado air, the bullpen badly needed a breather in the matinee against the Mets.

Arrieta got through eight innings in 101 pitches and came back out for the top of the ninth. He might have completed the game, too, if Mets rookie Pete Alonso hadn’t reached base on a line drive back to the mound.

“It was a good day,” Arrieta said after Hector Neris ended a ninth-inning tightrope walk by striking out Keon Broxton on a full-count, 94-mph fastball with the bases loaded.

“The curveball was good; the cutter was pretty good," Arrieta said. "I made an adjustment with that, getting the ball to change planes a little bit more. But really it boils down to forcing the issue early in the count, getting them to put the ball in play on the ground. That’s what I was able to do.”

It was vintage Arrieta. Using his signature sinker, he pitched to contact, recorded quick outs, and induced three double plays. He gave up four infield hits and only six hits overall. He didn’t allow a runner to reach third base until Michael Conforto’s leadoff homer in the seventh inning, when the Phillies had a three-run lead.

One big difference for Arrieta: He’s using his changeup more often -- and more effectively. It was his go-to off-speed pitch against the Mets. He turned to his changeup 21 times, and they put the ball in play only five times.

Arrieta attributes the improvement to a smoother delivery. Last season, his arm tended to drag behind his body. This year, with the adjustment to his arm angle and better timing in his delivery, he said he’s able to get on top of the ball and throw it with more downhill action.

“The changeup’s been great,” Arrieta said. “It’s a pitch for me where I know I can get swings-and-misses and weak contact. Last year, it wasn’t a really effective pitch because my hand was kind of tilted to the side, arm angle was slightly dropped, so it just didn’t have the effect. It started outside of the strike zone, and guys just laid off it.”

Armed with the revived changeup, Arrieta has been the rock in a rotation that is seeking consistency. Aaron Nola hasn’t come close to approximating the success that made him a Cy Young Award finalist last year. Nick Pivetta was optioned to triple-A Lehigh Valley before Wednesday’s game, signs of the young right-hander’s struggles and the contending Phillies’ prioritization of results over development at the major-league level.

Phillies starters have completed seven innings in only four of the first 17 games. Arrieta has done it three times. He has a 2.25 ERA.

“It certainly seems like he's taken the reins and taking the lead for our pitching staff right now,” Kapler said.

With Arrieta’s dominance, the Phillies won on a day when the offense wasn’t at its high-powered best. And as Arrieta walked off the mound in the ninth inning, the announced crowd of 39,861 rose to give him an ovation.

Arrieta is off to the start that the Phillies envisioned when spring training ended last month. The proof is in the pitching.