The Angels on Friday added pitching prospects Nate Smith, Keynan Middleton, Austin Adams and Eduardo Paredes to their 40-man roster, protecting them from next month's Rule 5 Draft.
To make room, the club designated for assignment right-handed pitchers Abel De Los Santos, Blake Parker and Jose Valdez and outrighted infielder Rey Navarro to Triple-A Salt Lake.
The Rule 5 Draft allows clubs who have not filled their 40-man rosters to select players from other teams who have not been designated to their 40-man rosters. Players who signed with their current club at 18 or younger and have played professionally for at least five years are eligible to be selected, as are those who signed at 19 or older and have at least four years of professional experience. Teams that select a player in the Rule 5 Draft must pay $50,000 to the player's original club as compensation and they must keep the player on their 40-man roster all season or the player must be offered back to the original club.
Smith, 25, is ranked by MLB Pipeline as the Angels' No. 5 prospect and is projected to compete for a job in Los Angeles' starting rotation in 2017. The left-hander can throw four pitches for strikes, highlighted by an above-average changeup. Smith struggled somewhat in 2016, going 8-9 over 26 starts for Salt Lake while recording a 4.61 ERA and a 1.40 WHIP.
Middleton, 23, is the Angels' No. 23 prospect. The right-hander pitched in 46 games while rapidly rising from Class A to Triple-A during 2016, compiling 88 strikeouts in 66 innings. His arsenal includes an fastball that can touch triple-digits with a developing put-away slider.
Adams, 25, pitched in 32 games in relief for Double-A Arkansas in 2016, posting a 3.05 ERA and going 4-for-5 in save opportunities.
Paredes, 21, pitched in 54 games while splitting time between Class A Advanced and Double-A. The right-hander posted a cumulative 3.33 ERA while striking out 75 batters over 70 1/3 innings.
The moves bring the Angels' 40-man roster to full capacity. The roster includes 25 pitchers, a figure that will likely be reduced by Opening Day.