SAN FRANCISCO — Joey Lucchesi realistically just needed to keep the Mets in their game into the middle innings Friday night to accomplish his mission.

The Mets got the bonus package.

The left-hander, appearing in a major league game for the first time in nearly two years, now holds the distinction of having pitched the team’s best game of the season, with seven shutout innings in the Mets’ 7-0 victory over the Giants at Oracle Park.

Lucchesi not only became the first Mets starting pitcher to record an out in the seventh inning this season, but also he placed an exclamation on his performance by striking out the side in the frame.

Overall, he struck out nine and allowed four hits and two walks over 97 pitches.

The strong outing provided a break for the Mets’ bullpen, which had been used extensively over the previous two games.

Lucchesi, 29, was recalled from Triple-A Syracuse before the game to fill Carlos Carrasco’s rotation spot.

Carrasco was placed on the injured list earlier in the week with a bone chip in his right elbow and received a cortisone shot.

His return will be predicated upon how well he can manage the elbow discomfort.

“I am super grateful to be up here with the team and be able to pitch like I did for the team,” said Lucchesi, a Bay Area native who estimated he had 50 family members and friends in attendance.

Lucchesi became the latest example of Mets starting pitching depth (following Tylor Megill, David Peterson and Jose Butto) to show he can hold his own.

Lucchesi had last pitched in the major leagues for the Mets in June 2021 before undergoing Tommy John surgery that cost him last season as he rehabbed.

“In ’21 I felt like I was kind of catching my rhythm and starting to throw hard after being traded over here from the Padres,” Lucchesi said. “Then I blew my arm out … fast forward to this outing, it was a grind, a lot of emotions. Just try to stay patient and wait for that moment. This moment for me was tonight and I am glad I dominated it.”

The replacements have excelled with Justin Verlander and Jose Quintana, in addition to Carrasco, on the IL. And the Mets will be without Max Scherzer for his next start, as he serves a 10-game suspension for violating MLB’s rules on foreign substances.

That start, Tuesday, could go to Butto, but only if he’s recalled to replace a player who is placed on the IL.

Butto otherwise must spend 15 days from last Monday, when he was optioned to Syracuse, in the minors.

“We will have four pitchers in the rotation we weren’t planning to break camp with,” manager Buck Showalter said. “It certainly says a lot about the work everybody in the front office and minor league system has done to keep us afloat.”

The Mets won for the seventh time in eight games on their California trip and have won eight of nine overall.

On the trip, they have outscored opponents 53-29.

Pete Alonso’s major league-leading 10th home run of the season, his second homer in as many games, staked Lucchesi to a 4-0 lead in the fifth inning.

Alonso cleared the fence in center field for a two-run blast against Anthony DeSclafani after a throwing error helped extend the inning.

Jeff McNeil hit a squib in front of the plate that catcher Joey Bart threw away, allowing Luis Guillorme to score from second.

Guillorme’s second single of the night had started the rally.

Alonso returned in the ninth with a two-run single, giving him four RBIs for a second straight game.

Daniel Vogelbach followed with an RBI single that brought in the Mets’ final run.

Guillorme delivered an RBI single in the second inning for the game’s first run.

Lucchesi received assistance from his defense, which turned two early double plays to help the left-hander escape trouble.

In the first, Lucchesi got J.D. Davis to hit into an inning-ending double play after Wilmer Flores’ double and a walk to Darin Ruf.

In the third, Flores hit into an inning-ending double play after Brett Wisely’s leadoff single.

In the sixth, Thairo Estrada singled leading off against Lucchesi, but Flores hit into another double play, the Giants’ third of the night.

“I did my homework and figured out who my ground ball [hitters] were,” Lucchesi said. “If I was in a jam I took deep breaths and executed my pitches most of all.”