Bill James is eager to see how the 2010 season turns out for defensive-minded Red Sox.

James, a senior adviser with the Red Sox since being hired after the 2002 season, believes that baseball now puts a greater emphasis on defense following a period that focused on on-base percentage.

“What I’m most curious about in 2010 is how much better we’re going to be defensively,’’ James told the Boston Globe. “I don’t think anyone questions that we’re going to have a better defensive team. But are we going to be as much better defensively as we want to believe we are, and is that going to have as much impact on [the pitching staff] as we hope it does?”

Since the Red Sox named Theo Epstein general manager in 2002 , the club has signed many undervalued players with high on-base percentages and OPS. These acquisitions include Kevin Millar, Bill Mueller and David Ortiz

“When one innovation plays itself out, the next one has to begin,’’ James told the Globe. “We were concerned several years ago that the advantage of the things that we knew could play itself out when you reach the point that everybody knew those things. Only [this] season will show whether we are keeping up or running in place."

The Red Sox have since shifted their emphasis to defense for the upcoming season. Signing Adrian Beltre, Mike Cameron, and Marco Scutaro is evidence of that, and James says the team will test their defensive measurements.

“We believe our defensive metrics are accurate,” James told “But I think you’d be a fool to say that we have the same confidence in them as we do offensive abilities. Defense, at this point, can be evaluated with the same degree of precision and the same degree of agreement among different methods as offense.”