Match ends, Arsenal 2, Manchester City 1.
Alexis Sanchez's scrambled extra-time winner secured Arsenal an FA Cup final date with Chelsea - and ensured Manchester City manager Pep Guardiola will end a season without a trophy for the first time in his coaching career.
Sanchez settled a contentious semi-final 11 minutes into the extra period after Manchester City failed to clear Mesut Ozil's free-kick.
Arsenal showed great resilience to come from behind - and eased the pressure on manager Arsene Wenger - after Sergio Aguero raced clear of Nacho Monreal to put City ahead in the 62nd minute.
Monreal made amends with the equaliser 11 minutes later as he drilled in Alex Oxlade-Chamberlain's cross at the far post - but City were left nursing a serious sense of injustice after this disappointing defeat.
They had a goal wrongly ruled out in the first half when Leroy Sane's cross was adjudged to have gone out before Aguero and Raheem Sterling combined to turn it into the net, while Yaya Toure and Fernandinho hit the woodwork after the break.
It left Arsenal victorious and Wenger aiming for a record seventh FA Cup triumph.
- Analysis: This is now Pep's biggest moment as Man City manager - Jenas
- Wenger lauds 'united' Gunners side
Wenger gets his statement of intent
Wenger's future - and the lack of clarity surrounding it - has only been brought into sharper focus by Arsenal's recent fall outside the Champions League places.
The manager needed a statement, as did his team, to ease the growing disquiet among Arsenal fans at the prospect that he will extend his stay as manager.
Arsenal's Wembley win against Manchester City will not ease the concerns in the minds of the doubters but he can point to the victory, and the manner in which it was achieved, as evidence that he could yet be the man to take the club forward.
Victory in the final on 27 May would strengthen his and Arsenal's case for continuity, but for now there was much for the Frenchman and his players to treasure about this triumph.
Wenger persisted with an unfamiliar three-man defensive system comprising youngster Rob Holding, Gabriel and Laurent Koscielny and set up his team to deliver an uncharacteristically stubborn performance.
Arsenal rode their luck at times - but Wenger will take that all day.
Wenger's players have been accused of not playing for him in recent months. No such accusation could be levelled here as they dug deep for victory.
The Gunners' embattled manager pumped his fists towards the skies at the final whistle and beamed with delight - he may yet achieve glory amid the worst discontent of his reign.
Were Manchester City robbed?
Manchester City will argue long and hard that their chances of reaching the final were sabotaged by a first-half decision that saw a good goal ruled out.
Referee's assistant Steve Child judged that Sane's cross had gone behind before Aguero turned it back at the far post and then Sterling made sure. Replays suggested the ball had not gone out and City were the victims of an injustice.
City will also feel Lady Luck deserted them as they lost playmaker David Silva to injury early on and saw those efforts from Toure and Fernandinho hit the woodwork.
In the final reckoning, they must also accept the brutal truth that once more they enjoyed superiority in possession and territory but could not find the ruthless touch.
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Guardiola faces a big challenge
Guardiola, arguably football's most celebrated coach, was brought to Manchester City to lift them to another level - and on that basis his first season without a trophy in a glittering managerial career will be regarded by many as a failure.
He has found it more difficult than he may have imagined after the seamless successes of his years in charge of Barcelona and Bayern Munich.
|Stick or twist?|
|Manchester City named an unchanged line-up under Pep Guardiola for the first time, in what was his 50th game in charge.|
|The three players who have started the most often are David Silva, Raheem Sterling and Kevin De Bruyne - 38 times each.|
|Another three players have started just once for Guardiola - Joe Hart, Tosin Adarabioyo and Angelino.|
He must now address the problems that have undermined City this season, particularly uncertainty over the goalkeeper position, where his decision to replace Joe Hart with Claudio Bravo has been unsuccessful, and also sort out an uncertain and ageing defence.
Guardiola's main priority now is securing a top-four place and getting into the Champions League, starting with Thursday's derby against Manchester United at Etihad Stadium.
Failure to achieve that objective is unthinkable.
Man of the match - Alex-Oxlade Chamberlain (Arsenal)
Perfect 20 for Arsenal - the key match stats
- Arsenal have reached their 20th FA Cup final, a competition record.
- This was Manchester City's first FA Cup semi-final defeat since 1932, also against Arsenal - the Citizens had won eight consecutively before this defeat.
- Alexis Sanchez is Arsenal's top scorer in games at Wembley, with four goals - he overtook Marc Overmars and Ian Wright on three.
- Sanchez has now been involved in more goals than any other Premier League player in all competitions this season (38, 24 goals and 14 assists).
- Sergio Aguero has scored 12 goals in his past 12 matches for Manchester City in all competitions.
- It was Aguero's second goal at Wembley, having netted for City against Chelsea in the FA Cup semi-final in April 2013.
- Nacho Monreal's last two goals for Arsenal have come in the FA Cup, both against Manchester clubs (having scored against Manchester United in March 2015).
- Alex Oxlade-Chamberlain has six assists in his past 10 FA Cup starts for Arsenal. In all competitions this season, only Mesut Ozil (10) and Alexis Sanchez (14) have more assists than Oxlade-Chamberlain (nine).
Manchester City return to Premier League action with a home derby against neighbours United on Thursday. Arsenal are at home to Leicester in the league on Wednesday.
- 15Oxlade-ChamberlainSubstituted forBellerínat 105+1'minutes
- 29XhakaBooked at 105mins
- 11ÖzilSubstituted forCoquelinat 119'minutes
- 7SánchezBooked at 25mins
- 12GiroudSubstituted forWelbeckat 83'minutes
- 30OtamendiBooked at 115mins
- 25FernandinhoBooked at 69minsSubstituted forRegesat 99'minutes
- 42Y Touré
- 17De BruyneBooked at 89mins
- 21SilvaSubstituted forSterlingat 23'minutesSubstituted forIheanachoat 105'minutes
- 19SanéBooked at 102mins
- 10AgüeroSubstituted forDelphat 99'minutesBooked at 105mins
- Craig Pawson
- Shots on Target
Second Half Extra Time ends, Arsenal 2, Manchester City 1.
Offside, Manchester City. Jesús Navas tries a through ball, but Kelechi Iheanacho is caught offside.
Substitution, Arsenal. Francis Coquelin replaces Mesut Özil.
Attempt missed. Yaya Touré (Manchester City) right footed shot from outside the box misses to the right. Assisted by Gaël Clichy.
Yaya Touré (Manchester City) wins a free kick in the attacking half.
Foul by Alexis Sánchez (Arsenal).
Nicolás Otamendi (Manchester City) is shown the yellow card for a bad foul.
Foul by Nicolás Otamendi (Manchester City).
Aaron Ramsey (Arsenal) wins a free kick on the left wing.
Attempt missed. Kevin De Bruyne (Manchester City) right footed shot from the right side of the box is close, but misses to the left. Assisted by Jesús Navas.
Kevin De Bruyne (Manchester City) wins a free kick in the attacking half.
Foul by Aaron Ramsey (Arsenal).
Attempt missed. Kelechi Iheanacho (Manchester City) header from the centre of the box misses to the right. Assisted by Kevin De Bruyne with a cross following a corner.
Corner, Manchester City. Conceded by Héctor Bellerín.
Attempt blocked. Fabian Delph (Manchester City) left footed shot from the centre of the box is blocked. Assisted by Kevin De Bruyne.
Attempt blocked. Yaya Touré (Manchester City) right footed shot from outside the box is blocked.
Gaël Clichy (Manchester City) wins a free kick in the attacking half.
Foul by Héctor Bellerín (Arsenal).
Attempt missed. Fabian Delph (Manchester City) left footed shot from outside the box misses to the right.