Along with Gennett, who is ranked by MLB.com as the club's No. 6 prospect, the Brewers added right-hander Hiram Burgos, their 2012 Minor League pitcher of the year, plus outfielder Josh Prince, right-handed pitcher Nick Bucci and outfielder Khris Davis (ranked No. 18). The Brewers' roster now stands at 39.
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.
Gennett, a 16th-round pick in the 2009 First-Year Player Draft who signed for an above-slot bonus, is undersized at 5-foot-9 but has hit his way up the Brewers' Minor League chain. He batted .293 with 30 doubles, five home runs, 44 RBIs and 11 steals at Double-A Huntsville last season and represented the Brewers in the All-Star Futures Game.
Gennett had a productive day in Kansas City, with a walk, double off the wall and two runs scored in four plate appearances. His U.S. squad defeated the World team, 17-5.
"Any time you get to face guys like that and put the ball in play and make something happen, you've got to be proud of yourself," Gennett said. "I'm pretty happy. It was a great experience. I've been able to meet some guys that I've heard a lot about, and they're all professionals. They go about their business the right way."
He boosted his prospect status in Spring Training, when the Brewers "borrowed" Gennett from Minor League camp to help cover some Cactus League games. He hit for the cycle in a game against the Royals and finished 9-for-20 (.450) with four extra-base hits in nine games.
Among Gennett's 2012 teammates was right-hander Burgos, 25, who was 10-4 with a 1.95 ERA in 27 starts and one relief appearance during a whirlwind season that began at Class A Brevard County and ended at Triple-A Nashville, one step from the Major Leagues. The Brewers were so confident in Burgos' ability that they instructed him to continue throwing after the Triple-A season ended, just in case an extra arm was needed during Milwaukee's surprise run to postseason contention.
Burgos was the Brewers' sixth-round Draft pick in '09.
Prince, who turns 25 in January, was Milwaukee's third-round pick in that same Draft but was not considered a premium prospect until this season -- when he converted from shortstop to the outfield, set career highs with 28 doubles, seven home runs and 55 RBIs at Huntsville while stealing 41 bases, then tore up the Arizona Fall League. He ranked second in the AFL with a .404 average and drove in 14 runs in 25 games.
"He made the most of his opportunity, I'll say that," Brewers assistant general manager Gord Ash said.
Davis, who turns 25 next month, played for Nashville during a 2012 season cut short by an early calf injury. He batted .350 overall in 82 games, with 15 homers and 52 RBIs, appeared in the AFL and is considered an offense-first prospect.
After battling early-season biceps tendinitis, Bucci was 3-3 with a 1.90 ERA in 10 starts between the Arizona Rookie League and Brevard County, then made six appearances in the AFL. He was an 18th-round Draft pick in 2008 but is only 22 years old.