When the Sharks come for the summer, they need a place to stay.

“Host families are our backbone,” general manager Jerry Murphy said. “Without them, we don’t have a team.”

Jessica Burnham is a two-year veteran of hosting; last year, she hosted two Sharks. She had followed the team from the get-go, when the organization was first founded, and was excited to be a fan of a the new Vineyard team (she didn’t miss a game all season). The experience hosting was so rewarding, she said, that she signed up again, taking in third baseman Eric Brenk, shortstop Matt Moore and pitcher Andrew Boyce. The players lived upstairs, as did Ms. Burnham’s daughter Martha, home from college for the summer, while Ms. Burnham made a “mom-cave” in the basement.

Dianne Powers, a first-year host, turned her attic into a four-man dorm room, which allowed for extra space when family came to visit in the summer.

“I had four, and I had a ball,” she said. “It was one of the most fun summers I’ve had.” Ms. Powers hosted pitcher Ryan Brockett, outfielder Cale Hansen, pitcher Matt Doyle, and catcher Nick Lanchesi, who left before the end of the season. Shortstop Dylan Tice took his place; a sixth player stayed with Ms. Powers later in the month, when he was working at the fair.

Host families are required to provide a place to sleep, access to the kitchen and access to laundry facilities, but, said Ms. Burnham, “I can’t do [just] that.”

“I treat them like my friends sent me their kid to stay. They’re part of the family,” she said.

Before the Sharks arrived, Ms. Burnham e-mailed the players and their parents to find out what sort of foods they liked, which led to “making Kool-Aid for the first time since the ‘70s.” Ms. Powers and her players scanned the Stop & Shop flyer each week for deals, as it is no easy task to feed one college student, let alone four.

“They’re athletes,” she said. “They need to eat.”

The end of the season and the departures of the summer guests came somewhat abruptly, with most players leaving within days of one another.

“My cat was in love with one of the kids,” Ms. Burnham said. “And she mourned.”