JOIN USBarcelona avoided any mishaps as they set out on the defence of their Spanish Cup title with a 3-0 first leg win away to lower league Alaves.
Despite resting several star names David Villa, Andres Iniesta and Cesc Fabregas were yesterday on target to continue the Catalan giants majestic start to the campaign which has seen them only drop points in La liga with their draw in the El Clasico with Real Madrid.
Lionel Messi, Xavi Hernandez and Pedro Rodriguez were among the players left at home in Barcelona but it made little difference as the visitors were always in control against an Alaves side which has seen better times.
The 2001 Uefa Cup finalists who lost to Liverpool are now in Segunda B, the Spanish third tier.
The Alaves keeper Urtzi Iturrioz was kept busy by an Alexis Sanchez header and a shot by Iniesta from the edge of the area before Villa fired Barca ahead on 40 minutes as he crashed a shot in off the crossbar after receiving a long ball from Iniesta.
The roles were reversed five minutes after the restart as Villa set up Iniesta for a curling 20-yard strike which nestled in the top corner.
Fabregas ensured a comfortable second leg at the Nou Camp with a header two minutes from the end.
Earlier Valencia overcame the rain and Segunda B Llagostera's artificial pitch for a 2-0 victory.
Valencia have had an inconsistent start to the season but they came out on top with goals from Jonas Goncalves at the end of the first half and Nelson Valdez after 68 minutes.
Llagostera held their own in a battling performance and Valencia barely deserved their lead from Jonas who failed to connect cleanly with a volley but it sneaked in the corner.
Valdez headed them further ahead and Llagostera wasted the chance to reduce the arrears with Marc Sellares missing from the penalty spot late on.
Walcott squeezed a shot over the line in the 95th minute to take the game to extra time, with Carl Jenkinson following up to make sure.
Reading's players were angry that more than the allotted four minutes of injury time had been played, and they were given further reason to curse their luck when Marouane Chamakh drove home to put Arsenal ahead in the 103rd minute.
Unbelievably, there was more drama to come.
Pavel Pogrebnyak headed in to make it 5-5 with five minutes to play but with penalties looming, Walcott slammed home to restore Arsenal's lead before Chamakh lobbed Federici to complete a remarkable evening of sport.
Although Reading fell short in the most agonising fashion, there were upsets elsewhere on Tuesday.
Second-tier Leeds United followed up their victory over Everton in round three to beat Premier League Southampton 3-0 and reach the last eight for the first time since 1996.
Middlesbrough, of the Championship, won 1-0 at top-tier neighbours Sunderland, while Bradford City of third-tier League Two overcame top-flight Wigan Athletic 4-2 on penalties after a 0-0 draw over 90 minutes.
There was no fairytale for League One Swindon Town, however. The former Premier League club, managed by Paolo Di Canio, fought back from 2-0 down to level with Premier League Aston Villa, only for Belgian striker Christian Benteke to hit a 90th-minute winner for the visitors.
Wednesday's stand-out tie sees Manchester United return to Chelsea three days after the stormy Premier League clash between the teams that culminated in accusations that referee Mark Clattenburg verbally abused Chelsea's players.
Liverpool coach Brendan Rodgers is set for his first meeting with Swansea City since leaving the South Wales club in the summer, while Norwich City host Tottenham Hotspur in another all-Premier League tie at Carrow Road.