Not only did the Mets enjoy a return to the friendly confines of Citi Field Friday after two games in Kansas City, they also took full advantage of their return to the friendly confines of the National League East.

After seven consecutive games spanning two seasons against the Royals, their home opener found them facing the miserable Phillies, who lost 99 games last season and are 0-4 this season after their 7-2 loss to the Mets. They were swept by the Reds in their opening three-game series.

There is no improvement in sight for the Phillies, which bodes well for the Mets as they seek to repeat their 2015 formula of beating up on divisional also-rans.

Nothing illustrated the Phillies’ haplessness quite as well as a play in the eighth inning, when it appeared they might be mounting a modest comeback attempt.

With runners on first and second and one out, Odubel Herrera hit a popup to the infield on which the umpire ruled an infield fly, meaning Herrera was out even when the wind-blown ball eluded third baseman David Wright.

Trouble was, Cesar Hernandez decided to run off first base — as is his right on an infield fly that is not caught — and easily was tagged out in a rundown to complete a double play and end the inning with the score 7-2.

advertisement | advertise on newsday

“That was unacceptable,” manager Pete Mackanin said afterward. “You can’t excuse that. That’s just not a smart play and he should know better. He’s an infielder. I know it’s cold and maybe he lost focus, but that’s unacceptable.”

When a reporter suggested that perhaps the call came late from the ump, Mackanin was having none of it.

“Even if he did, as an infielder, as a baseball player, you have to know what the rule is,” the manager said. “Cesar should have known better.”

Is the infield fly something the team goes over in spring training? “You shouldn’t have to,” Mackanin added. “In high school you should know that. It was just a brain cramp, I guess, that Cesar had.”

Speaking through an interpreter from his native Spanish, Hernandez said, “I did not see the umpire call the infield fly. I was trying to listen to my first base coach but couldn’t hear a thing because it was so loud.

Mets videos

“When the ball hit the ground I reacted to it. However, there are no excuses. I’m an infielder. I know the rules. I take full responsibility for it. It won’t happen again.”

Perhaps so, but the Phillies’ problems run far deeper than the occasional brain cramp. They are batting .212 and have scored 12 runs in their four losses.

“Guys are trying to do too much already,” said Mackanin, who felt his hitters were overswinging in an attempt to get to Mets starter Jacob deGrom. “I just have to get them to settle down and play the type of baseball they should be playing, like we did in spring training, and not try to do too much.

“We’re not the best hitting team in the league, but we’re certainly better than we’re showing. We swung the bats well in spring training. We’re going to hit the ball better. We just need to get something going. I need to keep everyone positive and not get down on themselves. Everybody’s trying so hard.”

The Phillies’ only extra base hit was a double by their pitcher, Jerad Eickhoff.

advertisement | advertise on newsday

“Without a doubt, I’m not pleased so far with the hitting,” the manager said. “We need to get the bats going and we need to get that bullpen in order and I think we’re going to be OK. We have to figure it out.”