Transfer Deadline Day: Premier League Round-Up
Colombia striker Falcao had been linked with a move away from the Stade Louis II throughout the transfer window, with Real Madrid touted as his most likely destination.
However, United swooped to land the 28-year-old in a lucrative season-long loan deal on Monday, with the former Atletico Madrid man set to partner Robin van Persie and Wayne Rooney in a stellar, new-look attack at Old Trafford.
One man Falcao will not play alongside is Danny Welbeck, after the England international completed a late move from United to Arsenal for a fee believed to be around £16million.
Another player to join Louis van Gaal's revolution at Old Trafford on deadline day was Daley Blind, who completed his £13.8m switch from Ajax.
Blind, 24, impressed for Van Gaal's Netherlands side at this year's World Cup, and the versatile, left-sided Dutchman will be expected to slot straight into United's starting XI.
While Manchester City, Liverpool, Chelsea, and Everton - who tried to sign United midfielder Tom Cleverley - were all quiet on the incomings front, QPR boss Harry Redknapp was typically busy.
Redknapp brought in former players Sandro from Tottenham, who he managed at White Hart Lane, and Niko Kranjcar.
However, his attempts to sign Fabio Borini from Liverpool and another ex-Spurs man, Jermain Defoe, were in vain.
Meanwhile, Hull City broke their transfer record to sign Uruguay striker Abel Hernandez, and Steve Bruce also brought in Hernandez's compatriot Gaston Ramirez on a season-long loan from Southampton as well as West Ham midfielder Mohamed Diame.
Out-of-favour Newcastle midfielder Hatem Ben Arfa also completed a loan move to Hull.
West Ham boss Sam Allardyce replaced Diame with Morgan Amalfitano from Marseille.
Neil Warnock made his first permanent signings since re-taking the reins at Crystal Palace by bringing in James McArthur from Wigan Athletic and Tottenham's Zeki Fryers.
Warnock also brought in Kevin Doyle on loan from Wolverhampton as Glenn Murray secured a shot-term move to Reading.
Sunderland signed two South Americans on season-long loans, with Uruguayan defender Sebastian Coates arriving from Liverpool and Argentina international Ricardo Alvarez coming in from Inter.
Tottenham added to their squad by recruiting Montpellier midfielder Benjamin Stambouli, while Oussama Assaidi has returned to Stoke City for another season-long loan deal from Liverpool.
Southampton beat the clock to sign defender Toby Alderweireld and winger Sadio Mane before the transfer window closed.
Elsewhere, Premier League new boys Burnley also bolstered their options with the permanent transfer of George Boyd from Hull City and Chelsea's Nathaniel Chalobah on loan.
Burnley also signed Michael Keane on loan from United.
Fellow promoted side Leicester City also raided United for Tom Lawrence and Nick Powell (loan).