Alvarez, who agreed to his slot value of $416,300, is a 6-foot-2, 215-pound right-hander who posted eight saves and a 0.72 ERA in 22 appearances during his junior season, holding batters to a .155 batting average while striking out 47 and walking 10 in 37 2/3 innings.
Alvarez, who boasts a heavy, high-90s fastball and an out-pitch breaking ball, started during his first two years in college before transitioning to the bullpen. His age (21), his collegiate experience and his makeup make Angels scouting director Ric Wilson believe he can be a "quick mover" in their system.
"He's not going to be a guy who's got to go step-by-step," said Wilson, who didn't have a pick in the first two rounds due to having loss those picks as compensation for the Albert Pujols and C.J. Wilson signings. "There's not a lot of refinement to him. Just get him headed up the system and see where he lands."
Others agreeing to terms were right-hander Mark Sappington (fifth round), shortstop Eric Stamets (sixth), catcher Andrew Patterson (seventh), catcher Zachary Wright (12th), center fielder Quintin Davis (20th), right-hander Pat Lowery (21st), center fielder Joel Capote (28th), catcher Zachary Livingston (34th), catcher Pedro Pizarro (35th) and right-hander Kenny Hatcher (36th).
Hatcher is the nephew of former Angels hitting coach Mickey Hatcher.
None of the Angels' Draft-pick signings agreed to more than their slot value, according to a source, with their picks from the top 10 rounds signing close to their slot value and the later picks mainly agreeing to figures below the slot recommendation.
Twenty-seven of the Angels' 38 Draft picks remain unsigned, including second baseman Alex Yarbrough, a fourth-rounder who was the Angels' second pick.
Alden Gonzalez is a reporter for MLB.com. Read his blog, Gonzo and "The Show", and follow him on Twitter @Alden_Gonzalez. This story was not subject to the approval of Major League Baseball or its clubs.