It’s a sunny day, perfect for baseball, in May 2008. Jordan Altdorfer stands in center field. He has never hit a curve ball, but he already has fans in high places. Two professional baseball players watch as he plays in one of his first T-ball games.

“Put your hat on, boy—look like a ballplayer!” yells Craig Stammen, a pitcher for the Potomac Nationals, one of the Washington Nationals’ minor-league teams. Jordan fields his first ball and throws it past the cutoff man as Stammen videotapes the five-year-old. After the game, Stammen and the Altdorfers pile into the family car and head to their home near Quantico.

For the past two seasons, Jeff and Laurie Altdorfer have hosted minor-league players, providing a rent-free place to come home to after long bus rides, cheap hotels, and rough starts.

Stammen is like a big brother to Jordan. Though he has gone on to become a promising starting pitcher for the Washington Nationals, he keeps in close touch with his former host family.

“From the moment I walked in the door, it was like I was family,” says Stammen, who showed up at Jordan’s seventh-birthday party this summer. “We talk all the time, and we’re constantly texting.”

Many minor-league players are far from home and fresh out of high school or college. They earn as little as $1,200 a month, but even players who get big signing bonuses—such as 2007 first-round pick Ross Detwiler—have lived with host families.

John Lannan, the Washington Nationals’ ace pitcher, spent part of the 2007 season living with Bill and Gail Annetti in Springfield while playing for Potomac. Lannan especially enjoyed cookouts after home games on Sundays and the fact that the family treated him like a regular guy. “It felt like home,” he says.

Nearly every player on the Potomac team lives with a host family, and some hosts take in four players at a time.

There are Ken and Karen Laverock, who specialize in hosting players who have a hard time finding homes. For the past ten years, the Laverocks have housed players who have wives, dogs, or both. Then there’s Jill Berman, an empty-nester who started hosting players when her sons went off to college. Jen Roy, a 28-year-old with a townhouse close to the Potomac Nationals’ stadium in Woodbridge, offers her two extra rooms to players who want something akin to a college experience. “It’s like having brothers,” she says.

Players attend family functions and eat dinner with their hosts when their schedules allow. Berman, who hosted Detwiler, bakes cookies for her players when they return from road trips. And one player became so addicted to Laurie Altdorfer’s chips and salsa that Jordan started calling him Mr. Chips.

There are ground rules. “I tell them, ‘Don’t bring any girls home that wouldn’t be good for my daughter to see,’ ” says Bill Annetti. “ ‘And don’t come home drunk.’ ”

Players aren’t immune from punishment. When Stammen ate the last of Jordan Altdorfer’s M&M’s, the five-year-old lectured him about taking other people’s food. Stammen bought him a new bag as a peace offering.

House rules were never a problem for Lannan—Bill Annetti says he’s one of the most focused players his family has hosted. On days Lannan pitched, he was unreachable. “I make two phone calls a day, one to my mom and one to my dad,” Lannan says. “Everyone else should know I’m not answering.”

Lannan was up-front with the family about his game-day routine. “He said when he first moved in, ‘I’m sorry if I’m a bit weird when I pitch, but I don’t answer my phone or talk to anyone after 2 pm,’ ” Bill Annetti says. “This is his job, and he needs to do whatever he can to succeed.”

But days when Lannan wasn’t pitching, he played Mario Kart with 13-year-old Katie Annetti or goofed around with the Annettis’ dog. “She would always bark at me,” Lannan says, “but I think she liked me.”

A host family’s life, like a ballplayer’s, can be unpredictable. Sometimes players will be with the team just a few weeks before they’re traded, released, or sent to another city. Bill Annetti says daughter Katie usually takes the news worse than the players do.

“It’s like she’s losing a big brother,” he says. “When they’re around, she has someone to look up to, someone to play video games with.”

When Lannan was promoted to the Harrisburg Senators, he joked with the Annettis about saving his room in case he got sent back to Potomac.

Seeing their charges reach the majors is a big source of pride for host families. Growing up in Pittsburgh, Jeff Altdorfer was a baseball fan from the time he could walk. He stayed up all night playing Strat-O-Matic baseball with his brother, learning the lineups of teams from the early 1900s, especially those of his beloved Pittsburgh Pirates.

Stammen moved in last season, his second stint with Potomac. “He whined about being in the bullpen,” says Laurie Altdorfer. But soon he was dominating the league and moved back into the starting rotation. He then was promoted to AA Harrisburg and from there to AAA Columbus. On May 21, Stammen was called up to the Nationals to make his big-league debut—against the Pirates. Jordan Altdorfer wore Stammen’s Potomac jersey to the game.