"We're elated that we were able to select him, get him signed and very excited about getting him in uniform," scouting director Ric Wilson said.
Newcomb, who was a junior at the University of Hartford, went 8-2 with a 1.25 ERA -- the seventh-best ERA in the NCAA -- in 14 starts as batters hit just .162 against him. He immediately becomes one of the top prospects in the Halos' farm system.
Wilson said Newcomb would probably start in rookie ball in Arizona but the Angels' top priority is to monitor his workload.
"It's important just to get him out and see what our system's like and hear from different guys in the organization," Wilson said.
General manager Jerry Dipoto has said that Newcomb would only throw about 30 innings the remainder of this season, regardless of when he signed. He threw 93 1/3 innings during his college season.
Newcomb, a 6-foot-5, 240-pounder originally from Middleboro, Mass., has a mid-90s fastball to go along with a curveball, slider and changeup.
One of three unsigned first-rounders entering Friday, Newcomb signed for less money than the Giants' Tyler Beede above him ($2,613,200) and Diamondbacks selection Touki Toussaint below him ($2,700,000).
Newcomb's bonus represented all the money the Angels had remaining in their Draft allotment, and the club avoided any tax or loss of future picks. The Halos had as much as $2,807,100 to spend on Newcomb without losing a first-round pick, though a 75 percent tax would have applied.
Newcomb was Los Angeles' first first-round selection since 2011, when first baseman C.J. Cron was selected with the No. 17 overall pick. The Angels lost their first-round picks in 2012 and '13 when they signed Albert Pujols and Josh Hamilton in respective offseasons.