In 2013, World Baseball Classic rules allowed a maximum of 15 position players on each team's final 28-man roster. Team USA carried 13.
For the 2017 WBC, Team USA could have as many as 14 or 15 position players.
One major reason: Many of the country's biggest stars are saying yes.
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A little more than two months before Team USA gathers for its spring camp in Florida, nine position players are locked in: catchers Buster Posey and Jonathan Lucroy; first baseman Eric Hosmer; second baseman Ian Kinsler; third baseman Nolan Arenado; shortstop Brandon Crawford; and outfielders Christian Yelich, Adam Jones and Andrew McCutchen.
Assuming tournament rules remain the same, that leaves a maximum of six spots remaining.
Video: MLB Tonight on Christian Yelich joining Team USA
Team USA officials have offered one of those spots to Matt Carpenter, a source said this week, although the Cardinals infielder has yet to commit. In 2016, Carpenter became the first player in Major League history to start at least 40 games each at first base, second base and third base during a season in which he hit 20 or more home runs. Manager Jim Leyland could use him at any of those positions or as a pinch-hitter -- although, admittedly, Team USA's everyday lineup won't include many matchup weaknesses.
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U.S. baseball officials also have strong interest in adding Daniel Murphy as an infielder and designated hitter. Murphy is regarded as one of the best pure hitters in the game, and, like Carpenter, he has a simple approach that should be effective at a time of year when players with more complex swings may not be in sync.
Outfielders Giancarlo Stanton and George Springer are known to be under consideration, although it's not clear yet if either will participate. (Springer also is eligible to play for Puerto Rico.) If Stanton and Springer both agree -- in addition to Carpenter and Murphy -- then Team USA would be up to 13 position players, leaving a maximum of two additional spots.
Video: Three-packs available for World Baseball Classic
Leyland has considered carrying a third catcher, likely a defensive-oriented player who would allow greater flexibility in using Posey or Lucroy as DH or off the bench. If Leyland decides to do that, the 15th and final spot could go to a versatile player (such as Ben Zobrist or Trea Turner) who can play shortstop if needed.
Barring injuries or late changes, that will be the core of Team USA. And while America's team at the 2006 WBC had superstar power -- notably Ken Griffey Jr., Derek Jeter and Alex Rodriguez -- the '17 edition should represent the deepest roster the U.S. has ever sent to a WBC.
Gregerson returns to U.S. 'pen
The expanded group of position players will be made possible by the approach Team USA general manager Joe Torre and Leyland are taking with the pitching staff. Torre and Leyland want to piggyback starting pitchers when possible, which will reduce the burden on relievers. Team USA has secured commitments from starters Max Scherzer, Chris Archer, Danny Duffy and Marcus Stroman, possibly with more to come.
Less is known about the bullpen's composition, although sources said this week that Astros reliever Luke Gregerson will return to Team USA after throwing two scoreless innings in the 2013 WBC. He joins Indians left-hander Andrew Miller and Orioles right-hander Mychal Givens among the known American relievers.
Gregerson will be the lone pitching holdover from the '13 WBC team, unless Craig Kimbrel, David Hernandez or Steve Cishek makes the U.S. roster.
In Israel, a chance to grow the game
As Team Israel prepares for its first WBC, Peter Kurz, the president of Israel's baseball federation, has arranged a trip that could change the country's sports history.
Next week, many Team Israel players, and their families, will travel to Israel. While there, they will hold public practices and dedicate a new field, in addition to visiting holy sites and meeting Israeli politicians. The delegation is expected to include Sam Fuld, Ty Kelly, Ike Davis, Ryan Lavarnway, Josh Zeid, Cody Decker, Jon Moscot, Corey Baker and Jeremy Bleich, along with Dodgers executive Gabe Kapler.
Video: Team Israel to take trip to Jerusalem before Classic
Team Israel's roster will consist largely of Jewish-American players; by WBC rules, players may compete for a country as long as they are eligible for citizenship.
"Being part of something that is truly bigger than any one player -- and bigger than the game itself -- is special," Decker said this week. "I hope we can inspire one more kid to pick up a baseball bat over there. All of us can't wait."
Scout on the field
Pete Orr is a Canadian baseball legend, having represented his country in the 2004 Summer Olympic Games, the '06, '09 and '13 World Baseball Classics, and the 2015 Pan-American Games, when he scored the gold medal-winning run ... on home soil ... in extra innings ... against Team USA.
Orr -- who played in the Majors with the Braves, Nationals and Phillies -- retired from professional baseball prior to Spring Training in 2016, having decided against playing another season at Triple-A. The only competitive baseball he played this year was on an MLB alumni team at the National Baseball Congress World Series.
Orr, 37, was a savvy player throughout his career and well-liked within the industry. Still, he was surprised when the Brewers offered him a pro scouting job in November. He accepted, but there was something else on his mind.
He wanted to play for Canada one last time.
The Brewers agreed, and Orr will conclude his career by joining Puerto Rico's Yadier Molina and Carlos Beltran in a select group of players to appear in all four WBCs.
"It's been nothing but an honor and privilege being a member of many different teams over the years," Orr wrote in an email. "From World Cup qualifiers that not too many people pay attention to, to the '04 Olympics, Pan Ams and WBCs - they have all been great. The teammates and staff are a true family for life. We have been a pretty close group."
Jon Paul Morosi is a national columnist for MLB.com.