Joe Bursik

Gabriel Martinelli scored a hat-trick as Arsenal came from behind to beat Portsmouth comfortably at Fratton Park and progressed to the FA Cup fourth round.

After FA Cup shocks involving Wrexham and Macclesfield earlier this weekend,

It looked as if the Gunners, who made 10 changes to their starting line-up, could be on the end of another when Colby Bishop put the Championship hosts ahead after three minutes.

But Arsenal were only behind for five minutes before Christian Norgard forced the ball in via Portsmouth's Andre Dizel after a trademark Gunners corner to level.

That goal settled the visitors down, and they took the lead from another set-piece when Martinelli flicked Noni Madueke's corner into the net after 25 minutes.

Maduke had a chance to add a third from the penalty spot, after he was brought down by Zach Swanson, but the England international dragged the ball wide.

Martinelli, who also hit the post and missed a good chance in the first half, added a third, after Gabriel Jesus played a low cross into the area following some quick thinking by Myles Lewis-Skelly and the Brazilian tapped in from close range.

Martinelli grabbed his third from another Arsenal corner, when the forward flicked the ball on from the near post and into the net.

There was then a piece of history when, at 16 years and 135 days, defender Marley Salmon became the youngest player to feature for the Gunners in the FA Cup.

Pompey keeper Joe Bursick had this to say about three goals from corners.

It's something they're strong at, and it's what gives them a three-goal win.

It's annoying and we need to sort them out, because we're conceding them in the league as well.

It needs to be better, and we need to address it, because it's costing us.

We'll look at it because it separates games you can look at the games where it's impacted us.

The team at the top of the Premier League are putting a lot of focus on it, so it shows how important it is.

It can be as simple as marking your man we need to be more aggressive.

If you are picking up your man you have to stay with it, but they are very good at it.

There's lots of blocks and you almost know where they are going to go but you can't do anything about it when you get blocked, and there are runners who free themselves.

You almost have to block the blocker and anticipate it but it does happen very quickly.

There's a lot of things to think about, and it isn't as easy as it seems, but there is an element of being against your man and being strong.