Arenado, who turns 21 on April 16, was one of six players sent out of Major League camp on Friday. The Rockies wanted to take a long look at him in camp, but were careful not to put pressure on him to break camp with the big club. Arenado had his moments, but also hit .192 with four doubles and five RBIs in 12 games.
Making it to the Majors would have been a push for Arenado, the club's second-round Draft pick in 2009 out of El Toro (Calif.) High School. The team invited him to camp as a non-roster player after a big 2011 season. He hit .298 with 20 home runs and led Minor Leaguers with 122 RBIs at Class-A Modesto, and followed that up by earning Most Valuable Player honors in the Arizona Fall League.
MLB.com named Arenado the No. 22 overall prospect in baseball this year and top prospect in the Rockies' system. It was the highest ranking of any third baseman. Arenado was ranked two spots ahead of the Rockies' next highest-rated player, left-handed pitcher Drew Pomeranz, 24, who is in line to begin the year in the club's starting rotation.
The Rockies did not immediately announce the level of the Minor Leagues that Arenado would begin this season, but he is most likely bound for Double-A Tulsa.
Officially, the Rockies optioned Arenado and right-handed pitcher Zach Putnam to the Minors and reassigned non-roster right-hander Carlos Torres, first baseman Chad Tracy (son of manager Jim Tracy) and outfielder Tim Wheeler -- another highly regarded prospect, who hit .263 with a home run and two RBIs in 14 games.
The Rockies had earlier optioned infielder DJ LeMahieu to the Minors, but kept him with the big club. However, LeMahieu was re-assigned to Minor League camp on Saturday.
The Rockies still have 39 players in Major League camp, including six non-roster invitees.