By Chris Harris at Wembley
It's never easy, is it?
Arsenal are heading back to Wembley for the FA Cup final - but they were stretched to the limit by Reading before booking their return trip.
Alexis scored the winner halfway through extra-time, his low shot squirming underneath Adam Federici and crossing the line before the Reading goalkeeper could retrieve it.
The Chilean had given Arsenal the lead in normal time too, applying a cool finish after Mesut Ozil had picked out his darting run. But Reading gave as good as they got and equalised when Wojciech Szczesny was unable to keep out Garath McCleary's shot.
Aaron Ramsey went closest to winning the game in 90 minutes, hitting the post from close range after a fine counter-attack. And so to extra-time, when Federici's luck ran out.
Arsenal and their fans are used to tense semi-finals - Wigan Athletic gave them plenty of anxious moments this time last year. But once again Arsene Wenger's team have prevailed, and a record 19th final appearance awaits.
Can they win the famous old trophy for a record 12th time? The omens are good - the last three times Arsenal have faced lower-league opposition in the last four, they’ve lifted the cup.
SETTING THE SCENE
The sun came out for the weekend's first FA Cup tie and Wenger, taking charge of his 10th semi-final, opted for three changes to his team.
Szczesny resumed his role as 'cup keeper' in place of current Premier League pick David Ospina, Mathieu Debuchy started his first game since the win over Stoke City in January, and Danny Welbeck, the matchwinner at Manchester United in the last round, stepped in for Olivier Giroud.
The form book hinted at a relatively comfortable win for the cup holders. Arsenal had won their last eight and 16 of their last 18; Reading were without a win in five and were taking a step up in class after reaching the last four without playing a top-flight side.
Last year's nerve-shredding encounter with Wigan was all the evidence Arsenal needed to take their latest Championship opponents seriously.
Arsenal's first job was to match Reading's endeavour. Predictably, Steve Clarke's indefatigable side harried and hustled from the first whistle, and the Gunners were knocked out of their stride in the early stages.
Alexis had the first shot of note, a improvised prod clipping a defender on its way over the bar. The resulting corner was met firmly by Per Mertesacker at the near post, but Federici got down well to save.
The Reading keeper was much further away from Arsenal's next effort, a beautifully-struck free-kick from Ozil which flew a yard wide with Federici grasping at thin air.
Szczesny was just as busy at the other end. Jordan Obita tested the Pole with a first-time effort from 20 yards, and Reading went close again when Nathaniel Chalobah's shot diverted off Mertesacker.
Reading were giving it a go in more ways than one - their muscular approach leaving its mark on Laurent Koscielny among others. Arsenal were focused enough but a flurry of misplaced passes demonstrated the pressure they were under.
That pressure lifted six minutes before the break.
Ozil, for once given time 25 yards from goal, spotted Alexis' clever run into the box and clipped a perfect pass towards him. The Chilean controlled with his thigh and readjusted his feet to poke a low shot through Federici's legs.
Arsenal were pegged back nine minutes after the restart.
Slick interplay on the left saw Pavel Pogrebnyak get to the byline and clip the ball back for McCleary. His first-time effort deflected off Kieran Gibbs and Szczesny couldn't get enough on his save to stop the ball crossing the line.
The blue-and-white half of Wembley went wild and underdogs had their tails up.
Mertesacker was forced off just after the hour mark, Gabriel slotting in alongside Koscielny. The Brazilian was straight into the thick of the action, meeting Ozil's corner with a powerful header that brought the best out of Federici.
That was a rare bright spot in a tough period that would have been worse if Daniel Williams hadn't sliced a golden chance wide from the edge of the box.
Giroud, boasting seven goals and four assists from his previous his 12 FA Cup appearances, replaced Welbeck with 20 minutes left. Within seconds, Gabriel spurned a free header after Ozil's free-kick found him unmarked six yards from goal.
Pogrebnyak and Ozil fired efforts off target as the tie entered its final 10 minutes, and Chalobah tested Szczesny from long range.
Arsenal needed a moment of inspiration and it almost came six minutes from time. Ozil released Alexis down the left, he found Giroud and he in turn picked out Ramsey, who held off a challenge to force a save from Federici. Ramsey looked poised to slam in the rebound but hit the post instead.
Cazorla shot over from the edge of the box as Arsenal started extra time brightly. But space was at a premium as Reading looked to protect what they had.
Wenger replaced Francis Coquelin with Theo Walcott but it was Ramsey who next went close, a rasping effort catching out Federici, who could only parry and watch anxiously as the ball looped over the bar.
Federici's next mistake was rather more costly. Ozil found Alexis scampering down the left channel but the Chilean's low shot looked eminently saveable. The Reading keeper allowed the ball to sneak under his body and over the line.
Jamie Mackie shot over after a fine run early in the second period of extra time but Arsenal looked strong on the break, and Giroud fired against a post with eight minutes left.
Reading weren't done but they were flagging, and the final whistle ended their brave resistance. Arsenal, elated and relieved, are Wembley-bound again.
Referee: Martin Atkinson
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