Here is every upset from this weekend's FA Cup third round, a notoriously tricky time for big clubs against lower-league opposition.
Nottingham Forest and Crystal Palace were the first Premier League teams to be dumped out of the famous competition, losing to Wrexham and Macclesfield respectively.
There were more surprise results, too, with teams lower down the pyramid suffering at the hands of unfancied rivals...
Macclesfield, 117 places lower than Palace, cause all-time shock
Macclesfield, who are 14th in the National League North, stunningly eliminated holders Crystal Palace who are 117 places above them in the football pyramid.
Macclesfield beat a young Palace side 2-1 on Saturday with goals from Paul Dawson and Isaac Buckley-Richards.
Yeremy Pino struck home a late free-kick to silence the home crowd but Macclesfield clung on for one of the FA Cup's biggest surprise results.
Wayne Rooney was in the stands at Macclesfield watching his brother John manage the home side in a huge upset.
Preston bemoan 'cow field, disgusting' in Wigan loss
Ryan Lowe was delighted after Wigan, of League One, upset his old club Preston, who are fourth in the Championship, with a 1-0 victory in the FA Cup third-round at Deepdale.
Harrison Bettoni's deflected 75th-minute strike proved decisive, while Callum Wright also missed a penalty late on for the visitors.
The Wigan boss said: "I'm pleased for our fans, pleased for our lads, the gameplan worked a treat. "I did enjoy it, of course, coming back to my old club and performing to the levels that we did, limiting them to very few chances, if any.
"[We] had three big chances and we should score more goals: the penalty obviously, and a couple of chances in the first half against a fantastic team who are flying high in the Championship so why wouldn't you be pleased? "There were nearly 4,000 of our fans in the away end and the outsang the Preston North End fans and it was fantastic."
Lowe was animated after the full-time whistle and played a parting swipe at Preston fans.
"It was a special moment and if [the fans] are going to give stick, you've got to be able to take it back and I relished that at the end of that game to give it back."
Preston boss Paul Heckingbottom said about the pitch: "It's a cow field. It's disgusting, that's what it is, but we have to play on it."
Wrexham beat Nottingham Forest on penalties
Phil Parkinson believes knocking Nottingham Forest out of the FA Cup will help Wrexham's push to play Premier League teams on an equal footing.
Wrexham won a thrilling third-round tie in front of Hollywood co-owner Ryan Reynolds on Friday night, progressing 4-3 on penalties at the SToK Cae Ras after drawing 3-3 over 120 minutes.
It was the first time Wrexham had met top flight-opposition since Reynolds and fellow owner Rob Mac took charge nearly five years ago and kick-started the Welsh club's journey from the National League to the Championship.
Wrexham manager Parkinson said: "This was another test against Premier League opposition and the next stage of our development is playing against these players.
"If you give them an inch you're going to get punished and they were clinical in those moments. We will analyse that and learn from it."
FA Cup scares avoided
Not every big club succumbed to lower-league opposition.
Antoine Semenyo made a goalscoring debut as Manchester City hit double figures in a 10-1 thrashing of League One side Exeter in the FA Cup third round.
ESPN's 'FC TV' crew react to Manchester City's 10-1 thrashing of Exeter City in the third round of the FA Cup.
Liam Rosenior was buoyed by watching his Chelsea side thrash Championship strugglers Charlton Athletic 5-1.
Wolves boss Rob Edwards believes his side are slowly improving after they cruised to a 6-1 victory over Shrewsbury in the Emirates FA Cup third round.
The Shrews had a hill to climb when Jorgen Strand Larsen and Jhon Arias put the hosts 2-0 up inside 11 minutes, but they were handed a lifeline when John Marquis tucked away a penalty after he was brought down by Arias.
However, Elyh Harrison gifted Strand Larsen a second before the break to restore Wolves' two-goal advantage and the Norwegian completed his first hat-trick for the club 13 minutes into the second half.
Rodrigo Gomes and Tolu Arokodare then both came off the bench and struck late to round off an emphatic result at Molineux.
Brentford cruised into the fourth round of the FA Cup after easing past crisis-club Sheffield Wednesday 2-0.
The Bees are flying in the Premier League under Keith Andrews this season and will now be eyeing a cup run after goals from Keane Lewis-Potter and Mathias Jensen earned them victory at Hillsborough.
Harry Wilson, Emile Smith Rowe and Kevin all scored in the second half as Fulham fought from behind to secure a 3-1 FA Cup victory against Championship side Middlesbrough.
Leeds United recovered from a goal down to beat Championship side Derby County 3-1. Wilfried Gnonto, Ao Tanaka and James Justin cancelled out the opener from Derby's Ben Brereton Diaz.
Ashley Barnes bagged a brace as Burnley put their Premier League worries on hold to cruise into the fourth round of the FA Cup with a 5-1 win over Millwall, who are in the Championship.
Marti Cifuentes praised Leicester's 'energy and desire' as they negotiated their FA Cup third round test at Cheltenham, winning 2-0.
The Foxes boss made eight changes to his line-up after their 2-1 Championship victory over West Brom on Monday and first-half goals from Patson Daka and Stephy Mavididi were enough to see off the challenge of the League Two hosts.
Southampton survived a scare on their way to snapping a six-game winless run with a hard-fought 3-2 victory at equally out-of-form Doncaster in the FA Cup third round.
The sides' first ever meeting in this competition offered Tonda Eckert's stumbling Saints the ideal chance to get back to winning ways after their recent Sky Bet Championship problems.
Southampton seemed set to cruise through after Cameron Bragg, Cameron Archer and Kuryu Matsuki scored first-half goals against the side 23rd in League One, only for Doncaster to expose familiar frailties.
Grant McCann's men, who also came into this without a win in six games, pulled back two goals through Matty Pearson and Jordan Gibson as visitors wobbled early in the second half.
However, debutant Daniel Peretz's double save in stoppage time helped Southampton avoid embarrassment in their commemorative yellow and blue kits marking 50 years since the club's sole FA Cup win.
Oxford's interim boss Craig Short was content to see his side see off League Two MK Dons on penalties in the FA Cup third round.
On the day the Us confirmed Matt Bloomfield as their new Head Coach, Oxford fell behind when MK Dons' Aaron Collins bundled home from a 34th-minute corner.
Will Lankshear equalised in the 52nd minute when MK Dons could not clear a long throw an, after both sides missed opportunities, the game went to penalties.
MK Dons' Jonathan Leko missed the target and Matt Ingram saved Connor Lemonheigh-Evans' kick to win the tie for Oxford, who reach round four for the first time since the 2019/20 season.
Jon Brady's first game in charge of Port Vale, of League One, ended in victory as the Valiants defeated League Two's Fleetwood 1-0.
Burton reached the FA Cup fourth round with a 5-0 win away at non-league Boreham Wood.
Another non-league club, National League South's Weston-super-Mare also came up short in a 3-2 defeat at Grimsby.
PA contributed to this report.