Manchester United are one of the most successful teams in the history of English football but even they are not immune to a giant-killing upset. 

The 12-time FA Cup winners have suffered their fair share of embarrassing results against clubs from the lower leagues. 

Ahead of their trip to League Two minnows Newport County in the fourth round on Sunday, we look back at when they were on the receiving end of shocks in the domestic cups. 

Man Utd 0-1 Southampton — 1976 FA Cup final

Arguably the biggest FA Cup final shock ever, nobody expected United to come unstuck against second-tier Southampton in 1976.

The Reds had finished third in the First Division and featured the likes of Lou Macari and Steve Coppell in their side but struggled to make the breakthrough at Wembley.

And as the Saints grew in confidence, they landed the killer blow. Bobby Stokes was the hero as he sneaked an effort past Alex Stepney to claim the the club's first major trophy.

Southend 1-0 Man Utd — 2006 League Cup fourth round

Not many clubs boast a 100% winning record against the Red Devils but Southend can claim that slice of history.

The Shrimpers were enjoying their first season as a second-tier side since 1997 when welcoming Alex Ferguson's stars to Roots Hall in the fourth round of the League Cup in 2006 — and marked that high point with a famous win.

Cristiano Ronaldo and Wayne Rooney played 90 minutes for the visitors but both were outshone by Freddy Eastwood, who curled in a beauty of a free-kick to earn the victory.

Man Utd 0-1 Leeds — 2010 FA Cup third round

Perhaps the most symbolic of these five results came in 2010 when third-tier Leeds, at their lowest ebb, won at Old Trafford.

Jermaine Beckford was the visitors' hero in the first renewal of this bitter rivalry for nearly six years.

The likes of Rooney, Dimitar Berbatov and Michael Owen did their best to level the tie but could not prevent Ferguson's men slumping to their first third-round exit in 23 years under the Scot.

MK Dons 4-0 Man Utd — 2014 League Cup second round

United's defeat at MK Dons in the second round of the 2014 League Cup was not even a close-run affair.

Louis van Gaal's visitors did not manage a shot on target until the 72nd minute of this humiliation, by which time they were 3-0 down and on their way out.

A team featuring David de Gea, Jonny Evans, Shinji Kagawa and Danny Welbeck went on to concede a fourth in an early sign of the troubled next decade the club have endured.

Man Utd 1-1 Middlesbrough (7-8 on pens) — 2022 FA Cup fourth round

A star-studded United team suffered another post-Ferguson disappointment when they were beaten on penalties by Championship outfit Middlesbrough at Old Trafford in the 2022 FA Cup.

Paul Pogba, Bruno Fernandes, Marcus Rashford and Ronaldo all started for Ralf Rangnick's hosts but could only muster a 1-1 draw across 120 minutes of action.

And Boro came out on top in an epic shootout as Anthony Elanga ballooned the decisive spot-kick over the top, plunging their hosts' woes to new depths.