Guerrero was part of the Spanish side that edged England to a 1-0 victory in the Summers World Cup final, albeit not taking to the field on that fateful day.
Nevertheless, the prominent midfielder joins Skinners side in a trade for Vilde Boe Risa, who despite her talents and international showcase at the Womens World Cup for Norway, has suffered a serious lack of game time in Red. Boe Risa was a fan favourite at United but the 28-year-old struggled to get a proper run out in league ties and instead was seemingly reserved for League Cup games.
Guerrero however has had a highly competitive season with Atletico Madrid before the move to England, starting 19 of her 23 games in La Liga.
The move was announced early on transfer deadline day, Guerrero said: I feel very happy and very privileged to be here. I am very proud to be part of the Manchester United family and look forward to achieving all our goals together.