Gabriel Martinelli responded to his recent criticism by scoring a hat-trick for Arsenal in their 4-1 comeback win over Portsmouth to reach the FA Cup fourth round.

The Brazilian winger was criticised for his response to Conor Bradley's season-ending injury on Thursday night - but played a big part in Arsenal scoring three goals from corners - to take their set-piece tally of the season to 22 in all competitions.

Mikel Arteta's side were, however, given an early scare by the Championship side as Colby Bishop slammed Pompey in front after just three minutes, after Kepa Arrizabalaga could only palm Conor Chaplin's strike from the edge of the box into his path.

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But Arsenal were back level five minutes later through their first corner of the game. Eberechi Eze's corner was flicked on a couple of times and while Christian Norgaard finished from close range to celebrate the goal, replays showed the ball went in off unfortunate Pompey defender Andre Dozzell.

It was Arsenal's fifth own goal in their last eight games in all competitions, while Portsmouth's set piece deficiencies are no surprise, given they have conceded the second-most goals from dead ball situations out of any Championship side this season.

So while Pompey threatened to retake the lead as Kepa saved well from Bishop and Chaplin - another Gunners set piece goal came with Arsenal's second corner of the game.

Noni Madueke's delivery was nodded in by Martinelli, who found the net to respond well to his criticism to the Bradley incident on Thursday night.

Arsenal should have added to their lead as Martinelli missed two good chances - including hitting the post from a couple of yards out with the goal gaping - while Madueke won a penalty to make it 3-1 off Zak Swanson, but put his effort from 12 yards wide.

That gave Portsmouth a bit of a lift and Chaplin could have equalised for the Championship side, only for Ben White to deny him with a good block.

And two minutes after that goal-saving challenge, Arsenal did make it three as Myles Lewis-Skelly released Gabriel Jesus down the right with a quick free kick - his cross was tapped home by Martinelli for an easy tap-in.

That allowed Arsenal to ring the changes as Kai Havertz returned for his first appearance since the opening game of the season. Marli Salmon also became the youngest Arsenal player in the FA Cup at 16 years and 135 days - but only after Martinelli had nodded another Madueke corner home, in a carbon copy goal from his first of the day.

The result puts Arsenal in Monday night's fourth round draw - as the Gunners' attention turns towards Wednesday's Carabao Cup semi-final first leg at Chelsea, live on Sky Sports.

Arteta: We had to defend our reputation here

Arsenal manager Mikel Arteta to TNT Sports:

"We started exactly how we didn't want to - giving them hope and momentum with an early goal. Then we started to turn things around, we were more dominant and scored a difference. Some positives to take, and the posit

"We made ten changes, there are certain things that are missing in cohesion. The level of rhythm you need in the way we play, it wasn't there. We weren't individually at certain levels, especially technically, to get out of their press. You have to do those basics much better than what we done.

"This [going behind] is part of the history of the competition, I have experienced myself both sides being in this game. One thing is being in the next round, the other thing is the club's reputation. You have to play with this mindset in these types of grounds.

"They [his fringe players] know they are all going to be important. We are doing that with facts, everyone has a chance to play and be involved. Everyone has to contribute and to achieve what we want."

Analysis: Arsenal have squad to go far in all four competitions

Arsenal are currently on a run of four away matches in four competitions across the next 10 days. The Christmas period may be over but the games are still coming thick and fast for the Gunners. But the Gunners' huge squad depth was on shown here.

Gabriel Martinelli's first senior hat-trick won them the cup tie but what's even more impressive is how sharp the Brazilian looked - he could have easily had one or two more against Portsmouth.

And it's no surprise really - he's only started two out of the last seven Premier League games. And that runs through the rest of the team too.

Arsenal made 10 changes from their tired team against Liverpool but still named a side including Gabriel Jesus, Noni Madueke, Eberechi Eze and Martinelli. Ben White, Kepa Arrizabalaga and Christian Norgaard brought experience at the back.

That squad depth is only getting stronger too. Kai Havertz's return was a huge plus for Arsenal, while the fact Bukayo Saka, Declan Rice, William Saliba, Leandro Trossard and Viktor Gyokeres could have the night off means they can be used for most of the Carabao Cup game at Chelsea on Wednesday.

Compare this situation to Liverpool's at Plymouth in the FA Cup last season. They could not name such a strong side against a relegation-threatened Championship side and went out to prioritise other tournaments.

Arsenal do have a few gaps - left-back and centre-back looks short amid their injuries - but barring that, they have a team capable of going quite far in four competitions.

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