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Unlike so many other sports, the vast majority of draft picks in Major League Baseball cannot be traded. There are, however, a few exceptions, and on Monday a trade between the Atlanta Braves and Kansas City Royals served as a reminder of that. 

The Braves sent three prospects -- center fielder Drew Waters, right-hander Andrew Hoffman, and corner infielder CJ Alexander -- to the Royals in exchange for the No. 35 overall pick in Sunday's draft, the teams announced. As well, the Braves add to their draft budget the $2.2021 million slot figure for that 35th pick. 

Unlike almost every other pick in the MLB Draft, this one was able to be traded because it's part of one of the two "competitive balance" rounds, one of which occurs between the first and second standard rounds and one of which is wedged between the second and third rounds. 

The picks of those competitive-balance rounds are distributed to small-market and low-revenue teams and can be traded, albeit only once. Outside of those 15 total competitive-balance selections, picks cannot be traded at all. 

As for the prospects involved, the 23-year-old Waters is a former consensus top-100 prospect who endured struggles last season, and he's blocked in Atlanta by standout rookie Michael Harris. Hoffman, 22, is a former 12th rounder who's pitched to a 2.36 ERA and 4.29 K/BB ratio in 15 starts this season for High-A Rome. Alexander, 26, is a bat-first corner defender with pop from the left side. This season, he's hit 15 home runs in 68 games for Double-A Mississippi.