MIAMI — Max Scherzer threw 100 pitches in his final spring training appearance with the idea it would leave him strong for the later innings in his Opening Day start.

“Unfortunately I gave up a couple of hits and I didn’t finish the game strong,” Scherzer said Thursday after the Mets’ 5-3 victory over the Marlins.

Scherzer rolled into the sixth inning, but surrendered doubles to Jacob Stallings and Luis Arraez that gave the Marlins their first run.

Then, with two outs, Garrett Cooper launched a two-run homer that tied the game.

The Mets regained the lead in their next at-bat and never relinquished it, giving Scherzer the win in his first Opening Day appearance for the Mets.

The right-hander became the first pitcher to start an Opening Day game for and against the Mets, whom he faced with the Nationals in 2015 and ’19 openers.

Overall he lasted six innings and allowed three earned runs on four hits and two walks with six strikeouts.

“Overall, pretty good,” Scherzer said. “I was executing pitches all day long. I ran into a little trouble there in the sixth, but the guys battled all day. I was getting run support.”