Hoffman was the Union's only Generation adidas player. As such, he did not count against the salary cap, and did not take up a budgeted player's slot on the roster.
"It has been truly an honor and blessing to wear the Blue and Gold," Hoffman tweeted after the trade was announced. He thanked the Union and fans "for all the love and support I have received since day 1 of joining the team. I wish all the fans and the organization nothing but the best."
As all 20 of the budgeted player slots on the Union's roster are currently occupied, it's unlikely that the Union would have been able to get a player from Los Angeles in the trade.
Hoffman will be in familiar territory when he heads to southern California, having played college soccer at UCLA.
Also, Hoffman likely will see significant playing time for the Galaxy under coach Bruce Arena. With attacking star Landon Donovan still on sabbatical, the rest of the Galaxy's forward corps is quite young.
Although Hoffman made only seven appearances for the Union last year, having a full year of professional experience could give the 22-year-old an edge on 18-year-old Jack McBean, 19-year-old Jose Villareal and 21-year-old Gyasi Zardes.
In addition, Zardes suffered a foot injury this month. If not for that, he might have been a candidate to start at forward alongside Robbie Keane, and the Galaxy might not have been in the trade market at this point.
Meanwhile, the Union also signed deals with SuperDraft selection Don Anding, supplemental pick Leo Fernandes and returning goalkeeper Chris Konopka, all of whom trained with the club this preseason. Anding was drafted as a forward out of Northeastern University. Fernandes is a 21-year-old midfielder from Stony Brook. Konopka, 27, of Toms River, N.J., spent last year with the Union.