Besides Watkins, right-handed pitcher Trey McNutt, infielder Christian Villanueva and right-handed pitcher Robert Whitenack were added to the Cubs' roster, which is now at 40.
Major League Baseball's deadline to protect players was Tuesday at 10:59 p.m. CT. Players first signed at age 18 must be added to 40-man rosters within five years or they become eligible to be drafted by other organizations through the Rule 5 process. Players signed at 19 years old are to be protected within four years.
Clubs pay $50,000 to select a player in the Rule 5 Draft, to be held on Dec. 6 at the conclusion of the Winter Meetings in Nashville, Tenn. If that player doesn't stay on the 25-man roster for the full season, he must be offered back to his former team for $25,000.
Among the players left unprotected was right-hander Nick Struck, who was the organization's 2012 Minor League Pitcher of the Year.
On Thursday, the Fukuoka SoftBank Hawks finalized a deal with LaHair for $4.5 million over two years, according to The Associated Press. LaHair, 30, who was considering playing in Japan prior to the 2012 season, batted .259 with 16 home runs and 40 RBIs in 130 games but lost the first-base job to rookie Anthony Rizzo.
The Cubs also announced right-handed pitcher Carlos Gutierrez, 26, who was claimed off waivers from the Twins on Oct. 24, has cleared waivers and been assigned outright to Triple-A Iowa.
Watkins, 23, a 21st-round pick in the 2008 First-Year Player Draft, batted .281 for Tennessee and finished second in the league in walks and triples. He led the league in runs scored (93) and compiled a 13-game hitting streak in June, collecting seven multihit games in that stretch.
McNutt, 23, has been considered a top prospect since he went 10-1 with a 2.48 ERA in 2010 for Class A Peoria, Daytona and Tennessee. In 2011, he was 5-6 with a 4.55 ERA in 23 games for the Smokies, and this season, went 9-8 with a 4.26 ERA in 34 games (17 starts).
Villanueva, 21, was acquired from the Rangers in the Ryan Dempster deal in July, and batted .279 for Class A Myrtle Beach and Daytona combined, with 14 home runs, 24 doubles and 68 RBIs. He was playing for Obregon in the Mexican Winter League. He began his Cubs career by hitting a home run in each of his first two at-bats in his first game with Daytona.
An eighth-round pick in 2009, Whitenack, who turned 24 on Tuesday, has been slowed after undergoing Tommy John surgery in 2011. He began the 2011 season 7-0 with a 1.93 ERA in 11 starts between Daytona and Tennessee, earning Southern League All-Star honors, before he was sidelined with an elbow injury.
Besides Struck, other players not protected include Frank Batista, 23, who converted 23 of his first 24 save opportunities for Tennessee. A Southern League All-Star, he compiled a 2.22 ERA in 43 games, but did struggle in a brief stint with Triple-A Iowa, posting a 5.87 ERA in six games.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.