No matter how many baseball games you might attend, each holds the possibility of seeing something never seen before.

A player’s first career homer. A pitcher hitting a homer. Both are unique — the ladder more so now. Countless pitchers have a home run on their statistical ledger. One stands alone.

Bartolo Colón was a terrible hitting pitcher even by hitting pitcher standards. Looking at his stat line is like staring at the sun. In 299 career at-bats, he struck out 166 times. His slash line: .084/.092/.107. It’s not like he had the physical build to luck into any infield hits.

Statistics, though, don’t convey the sheer ineptitude by which Colón had performed in the batter’s box. He gradually improved over time —making contact, hitting singles, even hitting doubles. But nobody — literally nobody — expected what took place against James Shields.

Colón came to the plate in the second inning after Kevin Plawecki delivered a two-out double. The right-hander, who hadn’t recorded a hit yet on the season, took a swing at Shields’ 1-1 pitch. Contact was made. The ball had lift. It carried to left field. And what seemed as likely as lighting striking in San Diego, it landed over the left-field wall.

The reaction — from the Mets dugout, from The 7 Line congregation gathered in right field, from Gary Cohen and Ron Darling on television, from Howie Rose on radio — was utter joy mixed with disbelief. Shields, meanwhile, may never live it down.

Colón carried his bat up the first base line as he watched the ball fly, then proceeded on his maiden home run trot. Whether it was accidental or not, Colón took a — shall we say — leisurely stroll around the basepaths (clocked in at 30.6 seconds). Nobody would give him the “act like you’ve been there before” criticism. That gave his teammates enough time to vacate the premises. When Colon crossed the plate, the only ones left there to greet him were Plawecki, on-deck hitter Curtis Granderson, No. 2 hitter David Wright, and manager Terry Collins on the edge of the dugout.

Once the “silent treatment” was done, players joyously celebrated around their lovable pitcher.

“I don’t even know how to explain it,” said Colón who began his career way back in 1997. “Once I hit it, I knew it was gone.” Spoken like a true power hitter.

Did we mention he was 17 days shy of his 43rd birthday? That made him the oldest major leaguer to hit the first home run of his career.

The Mets went on to win, 6-3. Colón pitched into the seventh inning and earned the victory, the 221st of his career and the third of 15 that year — his last as a New York Met. In his three seasons, Colón was a reliable part of the rotation. He never pitched fewer than 191.2 innings. He was a respected veteran among teammates and beloved figure among fans.

But May 7, 2016 became the defining moment of his Mets career. With the advent of the universal designated hitter, it’s likely we’ll never see anything like it again.