Joe Hart prevented an FA Cup embarrassment for West Ham United on his return to Shrewsbury Town.
Paul Hurst's promotion challengers created numerous chances to have become the second giantkillers of the day after Newport County from League Two beat Championship side Leeds United 2-1.
But they were kept in it by their goalkeeper Hart, who started his career with the hosts and made two flying saves, while Jon Nolan wasted a golden chance at the death.
Shrewsbury were handed a boost before the game with the news that goalkeeper Dean Henderson – on loan from Manchester United – had been given the chance to play after being prevented from figuring in the first two rounds.
By contrast Hart seemed ill prepared on his return to his home town.
In 21 year at Arsenal Wenger has never – ever – lost in the third round of the competition and has won the FA Cup in three of the last four seasons, but Arsenal were rarely in this tie. They fielded a hugely weakened team – nine changes – but this was an older and vastly more experienced, and obviously expensive, team than Forest could put out.
It was a rollicking cup tie with Forest preying on the Arsenal defence from the start. In the first half they scored twice and could have scored even more but for goalkeeper David Ospina making three sharp saves.
Both Forest goals were claimed by Eric Lichaj – and the 29-year-old American full-back had only scored seven career goals before this match. Both goals were well-worked. The second was simply stunning. For the first Forest won a free-kick down their right which was driven in hard and left-footed by Dowell with Lichaj charging in to head home from just a yard out in front of Ospina. The inquest began. Where were the Arsenal defenders? Was Ospina slow to react?
The goalkeeper was certainly not at fault for the second. Again, this time just before half-time, it was down the Forest right with the impressive Matty Cash crossing and Theo Walcott heading out under pressure from striker Ben Brereton with the ball looping out of the area for Lichaj to run in, chest down and place a volley, arcing high into the net. Again his celebrations were exuberant.
Arsenal had quickly drawn level after Lichaj’s first goal with a free-kick swung in by Walcott and headed against the post by Rob Holding with Per Mertesacker reacting first to stab the ball home. But it was Forest creating the opportunities with Brereton taking advantage of Arsenal’s unwise decision to play a high defensive line. The 18-year-old is, after all, 15 years younger than Mertesacker. And it showed.
Before they opened the scoring Forest broke quickly, with Ben Osborn’s driven effort charged down and the rebound ricocheting across the penalty area to Cash whose low cross-shot was finger-tipped around the post by Ospina. Then the Colombian excelled again as Brereton was put through by Cash, ran away from Holding, and easily cut across Mertesacker – who simply could not respond – with Ospina parrying the striker’s shot.
Holders Arsenal were sent crashing out of the FA Cup at the first hurdle, as they suffered a 4-2 defeat to Championship side Nottingham Forest.
An enthralling, action-packed clash at the City Ground saw the Gunners lose in the third round for the first time under Arsene Wenger, as England's longest-serving manager was out-witted by Forest caretaker boss Gary Brazil.
American full-back Eric Lichaj opened the scoring before Gunners skipper Per Mertesacker levelled.
Lichaj deservedly re-established Forest's lead before the break when he fired in a stunning volley to give the home fans hope of an upset as they got stuck into their half-time Bovrils.
Impressive teenager Ben Brereton netted a penalty to put the hosts 3-1 up before a Danny Welbeck shot trickled in.
But a controversial spot kick from Kieran Dowell - who appeared to kick the ball twice as he slipped taking the penalty - sealed a 4-2 win and a famous upset for the hosts.
Wenger - who has lifted the trophy seven time - was forced to watch the action unfold from the stands as he began a three-match touchline ban, as he lived to regret making nine changes from the side that took on Chelsea midweek.
Recap all of the action as it happened below...
Nottingham Forest dumped the holders of the FA Cup out of the competition in a breathless game that included a goal for the ages, two penalties and a red card
