Ain’t no party like a pre-World Series slumber party.

Kevin Millar and David Ortiz made their triumphant return to Fenway Park on Wednesday night when they and other members of the 2004 World Series champion Boston Red Sox threw out the ceremonial first pitch before Game 2 of the World Series at Fenway Park.

But it turns out Millar and Ortiz had convened well before that moment by channeling their inner middle schoolers. Speaking Wednesday on Barstool Radio before Game 2, Millar regaled listeners with a tale of his impromptu sleepover at his former teammate’s house Monday night.

Here’s what happened, according to Millar: After landing in Boston on Monday night, he and his wife met up with former utility man-turned-broadcaster Mark DeRosa and his wife, Heidi, for a drink. They then headed to Ortiz’s restaurant, Yvonne’s, and “had a few cocktails.”

As Ortiz was taking them back to their hotel, he turned to Millar and said, “Just sleep over.” And after the wives gave approval, the party was on.

“And so we rolled out, just slept over,” Millar said. “Like literally slept over. Stayed up till 4:30 (a.m.), had a great time.”

No word on if video games or pillow fights were involved.

If the sleepover session was meant as a good luck charm, it worked: Boston took Games 1 and 2 from the Los Angeles Dodgers at Fenway to move within two games of its fourth World Series title of the 21st century.

Thumbnail photo via Bob DeChiara/USA TODAY Sports Images