: Premier League clubs Watford and Hull City, and Championship side Leeds United paid the penalty for fielding weakened teams when they were all knocked out of the FA Cup in the fourth round on Sunday -- but holders Manchester United won comfortably.
Like Liverpool, beaten at home by Wolverhampton Wanderers on Saturday, the three beaten sides miscalculated in resting so many players ahead of league games in midweek and could have no complaints at going out of the competition.
Yet United went through, winning 4-0 despite making nine changes at home to Wigan Athletic, who are in the bottom three of the Championship.
Watford lost 1-0 to League One (third tier) side Millwall and Hull, FA Cup finalists three years ago, were humbled 4-1 by Championship (second tier) side Fulham after missing two late penalties.
Leeds, fourth in the Championship and giving greater priority to returning to the Premier League after a 13-year absence, lost 1-0 to Sutton United, who joined fellow fifth-tier National League club Lincoln City in the last 16.
It is the first time two non-League clubs have progressed that far since the competition was reorganised more than 90 years ago.
At Old Trafford, Marouane Felliani broke Wigan's dogged resistance in the 43rd minute by heading in a cross from former German international Bastian Schweinsteiger, making a rare appearance.
Anthony Martial, criticised by manager Jose Mourinho last week, then set up goals for Chris Smalling and Henrikh Mkhitaryan before Schweinsteiger added United's fourth.
"The first half was not very, very good but we managed to be 1-0 in front," Mourinho said. "The second half was much better and the job was done."
Millwall, who beat another understrength Premier League team, Bournemouth, in the previous round, fully deserved the win earned for them with a goal by Steve Morison in the 85th minute.
Watford's manager Walter Mazzarri had made seven changes, leaving experienced players like captain Troy Deeney and midfielders Etienne Capoue and Tom Cleverley among the substitutes.
They also lost goalkeeper Costel Pantilimon to injury just before halftime.
Manager Neil Harris felt his mid-table League One team fully deserved their victory over a side 40 places above them.
"We could easily have been three or four up by halftime," he said.
"This club and this team epitomise what the FA Cup is all about."
At Craven Cottage on the bank of the River Thames, Hull, who had made six changes, fell behind to a goal by their former forward Sone Aluko after 16 minutes.
Evandro headed an equaliser four minutes into the second half, but Chris Martin, on loan from Derby County, soon restored the lead.
Promising youngster Ryan Sessegnon added a third goal and with 12 minutes left Stefan Johansen scored a fourth.
Hull's Abel Hernandez then had two penalties saved by goalkeeper Marcus Bettinelli in the space of a minute to round off a bad day.
"We have to do many, many things before the transfer window closes on Tuesday," their manager Marco Silva said.
Former European Cup finalists Leeds, out of the top flight of English football since 2004, fielded almost a complete reserve team on the artificial pitch at Sutton and found the non-Leaguers, 84 places below them, too strong.
Captain Jamie Collins scored the only goal from a penalty after 53 minutes and Leeds finished with only 10 men when their own captain, Liam Cooper, was sent off near the end.
Leeds manager Garry Monk admitted he had made too many changes to the regular team.
His opposite number, Paul Doswell, said the result and financial benefits from live television coverage were a "life-changer" for the 118-year-old club.