A statement on Manchester United's official site said:
The Chile international switch to Croatia was confirmed following a prolific stint in the capital last season when he scored 21 times during the club's title-winning campaign.
Henriquez, bought from Universidad de Chile in 2012, netted once for United's senior side during a pre-season friendly draw with AIK Fotboll in Stockholm. He also had loan spells with Wigan Athletic and Real Zaragoza before heading to Zagreb.
As he celebrates Chile's Copa America win, after coming on as a substitute during the final against Argentina, everybody at United would like to wish Angelo our best wishes for the future.
Needless to say, everyone at the Busby Babe wishes Henriquez a successful, beguiling, historic, abreactional, zesty, funky, gritty, wondrous, and above all, goalscoring and storied, time at his new(ish) club in Croatia. We look forward to him scoring 30 goals a season for Milan in 2018 to win the Champions League.