Arsenal Need Extra Time to Beat Manchester City 2-1 in FA Cup Semi-Final

Arsenal qualified for the final of the 2017 FA Cup on Sunday by beating Manchester City 2-1 in extra time at Wembley Stadium.

Sergio Aguero opened the scoring after 62 minutes thanks to some dodgy defending and a mistake by goalkeeper Petr Cech. Nacho Monreal blasted home the equaliser shortly after, and neither team scored again in regulation.

In extra time, Alexis Sanchez put his team ahead, and the Gunners held on.

As shared by Arsenal's Twitter account, the Gunners once again used their new formation with three defenders:

Raheem Sterling did not make the Citizens' starting XI:

City took control of possession early, but Arsenal's formation did its job in the opening stages, limiting space through the centre and isolating Aguero. Chances were few, with Olivier Giroud sending a tame header into the hands of Claudio Bravo.

David Silva put Cech to work with a sharp shot when he got away from his marker, but the Spaniard took a brutal beating and lasted only 23 minutes before he left the pitch with a knock.

Per Sam Tighe of Bleacher Report, Silva takes way more hits than people care to acknowledge:

Laurent Koscielny had a goal ruled out for offside, and replays showed the linesman made the right call. Shortly after, Aguero wanted a penalty after contact with Alex Oxlade-Chamberlain, but the official was unmoved.

Per Stuart Brennan of the Manchester Evening News, the Argentinian was at least partially responsible for his own tumble:

Aguero fired a shot into the side netting before it was City's turn to have a goal ruled out, and this one was far more controversial. Leroy Sane picked out Aguero with a cross, and the striker thumped home a volley. The linesman claimed the cross went over the line prior to reaching Aguero, however, though TV replays showed it didn't.

Former England international Gary Lineker felt for the official:

Bleacher Report's Nick Akerman weighed in on the latest controversy:

Nicolas Otamendi had a great chance to open the scoring early in the second half, but he sent his close-range header wide. On the other side of the pitch, Bravo nearly cost his team dearly when he slipped on the ball, but he managed to clear it just in time.

Arsenal found more space to work with after the break, and Giroud had a few looks on goal, but City opened the scoring courtesy of a great finish by Aguero and some sloppy goalkeeping by Cech.

The veteran didn't leave his line in time to capitalise on Aguero's bad first touch, and his inaction cost the Gunners. Miguel Delaney of the Independent thought he hesitated:

Mesut Ozil almost had an immediate response, as he curled a shot inches wide of the post. The Gunners pushed for an equaliser with plenty of men inside the City half, and they were rewarded when Monreal turned home a cross from Oxlade-Chamberlain.

Per Tighe, the latter appears to be the main beneficiary in the new formation:

It was then City's turn to take control of the ball again, and Cech redeemed himself with a superb fingertip save, pushing a shot from Yaya Toure onto the post.

The pace ramped up again as the end of the match drew near, with Ozil taking too long to get a shot off and wasting a chance and Fernandinho hitting the crossbar from a dangerous corner.

Substitute Danny Welbeck went close as well, with his strike missing by inches, but neither team was willing to go all-out late, leading to extra time. ESPN FC's Mattias Karen was fine with that:

Arsenal had the fresher legs in the first half of the added period, and Rob Holding had a chance to add to the score, but he sent a header over the bar. But Sanchez broke the deadlock, easily converting after City failed to clear a dangerous cross.

Per Karen, it was a flashback to 2015:

Welbeck perhaps should have killed the match with the last chance of the first session, but he missed from close range with a header.

Manager Pep Guardiola used his final substitution to bring on Kelechi Iheanacho in the second period, but it was another substitute who went close, with Fabian Delph too late to pull the trigger. Also, Kevin De Bruyne fired a late strike wide before the official put an end to the match.

Arsenal will host Leicester City on Wednesday, while City's next outing will be the derby against Manchester United on Thursday.