There are six days left in the major league free-agent filing period, but the Boston Red Sox already have made their first interesting move of the offseason.

The Sox have hired baseball historian and statistical expert Bill James as a senior adviser. The Lawrence author is best known for books such as “The Bill James Historical Baseball Abstract” and “Win Shares.”

“I’m very excited because I’m working with very bright people who have a very good chance to be successful,” James said Wednesday.

James declined to discuss his salary or the details of his role because he won’t be formally introduced until a news conference next Friday in Boston.

Fans of James’ work shouldn’t worry about his new career interfering with his old one.

“I’ll continue to write books,” he said. “It’s a substantial amount of time and effort, but the arrangement will allow me to work on other things.”

James said he was uncertain what his next book would be. For the first time since 1980, he’s not under contract with a publisher because he decided “to write a book before I sell it.”

“I was determined not to get back in a situation where I had to do a book for somebody, so instead I got into a situation where I owe somebody a long report every few months,” he said.

James will continue to live in Lawrence and will travel to Boston several times a year.

This isn’t the first time he’s worked in baseball outside the publishing world. He worked as a consultant for the Kansas City Royals in the late 1990s. From the late 1970s to the early 1990s, James worked for sports agents, providing information to help players in negotiations.

James said he liked dealing with players, but this time he will work for management.

“He’s a brilliant thinker and he spends a good deal of his time thinking about baseball,” Red Sox assistant general manager Theo Epstein told the Hartford Courant. “He has a lot of ideas how to use players, what players potentially to acquire. He thinks about the game the way a fan does and a front office mind, as well.

“We’re going to bounce ideas off him. I think he’ll probably be proactive in suggesting ideas. We want to be the best scouting operations in baseball and we want to be the best objective analysis operation in baseball as well. Someone like Bill James helps us on the second front.”