Nelson, the Brewers' eighth-best prospect, found out via a tweet from Brewers senior director of media relations Mike Vassallo that he will be Milwaukee's representative in the Sirius XM All-Star Futures Game.
"We had an off-day yesterday so I went down to Huntsville, [Tenn.]," Nelson said. "I was running a few errands and it was a good little surprise."
The 24-year-old will be part of a U.S. Team that takes on the World Team on July 14 in the 15th annual showcase of prospect talent the Sunday before the All-Star Game.
Nelson has worked his way up the Brewers' farm system since he was selected in the second round of the 2010 First-Year Player Draft. He jumped from Class A Brevard County to Double-A Huntsville last season, and made the jump to Triple-A Nashville this month.
The hard-throwing Nelson has made three starts with Nashville and is 0-2, but he has a 3.00 ERA. In 12 starts with Huntsville, Nelson went 5-4 with a 2.74 ERA and 72 strikeouts against 15 walks in 69 innings.
He said the biggest change from a year ago is with his command, as he struck out 119 batters but walked 62 in 127 1/3 innings in 23 starts between Brevard County and Huntsville in 2012.
"The big thing with me at the end of the year last year was walks, obviously. I walked too many guys towards the second half of the season," Nelson said. "It was mechanical, a little mental and also physical, just being healthy and stuff.
"This year I just have the mentality that I'd rather give up a ground-ball hit than a walk. Make the other guy earn it. More times than not, you'll see that you'll go deeper in games, your pitch count will be lower."
The Brewers have four former Futures Game players on their current roster in Rickie Weeks (2004), Ryan Braun and Yovani Gallardo ('06) and Jean Segura ('12).
Segura represented the Angels last year and the Brewers' representative Scooter Gennett spent about three weeks with the team this season before getting optioned to Nashville on Wednesday.
"I always watch the All-Star game and it's something I've always seen and dreamed of being there," Nelson said. "It's going to be exciting to be there as a futures All-Star and hopefully there some day as a big leaguer."
The 15th annual SiriusXM All-Star Futures Game takes place at 1 p.m. CT on All-Star Sunday at Citi Field in New York and can be seen live on MLB.com, ESPN2 and ESPN2 HD and followed live on MLB.com's Gameday. In addition, XM Radio will broadcast play-by-play coverage of the event live on MLB Network Radio XM 89. MLB.com will also provide complete coverage before, during and after the game. Fans can stay updated by following @MLBFutures on Twitter and can send/receive tweets to/from the U.S. and World Team dugouts during the game by tagging tweets with the hashtags #USDugout and #WorldDugout.
Also, for the first time, fans will determine the final player on the U.S. and World Team rosters by casting their votes in the All-Star Sunday Futures Finalists ballot. There are five candidates for each team, and voting ends on Sunday at 10:59 p.m. CT.