Fernando Tatis Jr. has now allowed more home runs than he’s tallied.

The slumping Padres outfielder’s miserable season continued Friday night when his error led to a Little League grand slam for the Cardinals’ JJ Wetherholt in San Diego’s 6-0 home loss.

Tatis’ error turned what should have been at most a two-run single into a single that cleared the bases and gave the Cardinals a 4-0 lead in the fifth inning.

The two-time Gold Glove-winning right fielder simply whiffed while running forward, with the ball going completely under his glove and rolling all the way to the right field wall.

Wetherholt didn’t even have to slide to notch his four-bagger.

“He’s a playmaker, just trying to make a play,” Padres manager Craig Stammen said, per MLB.com. “He just came up short.”

Tatis is normally a surefire defender, with two Gold Gloves in the last three years, including last season, and it’s possible his struggles at the plate are starting to weigh on him.

It’s one thing for a player to struggle at the plate, but it’s another if the problems affect other facets.

For as bad an error as this may have been, though, it marked just his first of the season.

After Friday’s 0-for-2, the 27-year-old has not homered in 158 plate appearances and 137 at-bats spanning 37 games, the longest drought of his career, according to MLB.com.

He’s tallied at least 17 homers in each season, including 25 last season.

Tatis is posting his career-worst slash line of .248/.318/.299, and has just 13 RBIs. His .618 OPS is noticeably below his career .855 mark.

The Padres (22-16) have managed to still be one of the best teams in the sport despite his struggles.

“He’s coming in trying to make a play, trying to throw the guy out,” Stammen said, according to MLB.com.

“Things like that happen. He’s not a perfect player. Nobody’s a perfect player. Even the best players in the world make mistakes.”