Arsenal's mindset was the most pleasing aspect of their 4-1 FA Cup triumph over Portsmouth, so says Mikel Arteta.

Gabriel Martinelli netted a hat-trick – becoming the first player to do so for Arsenal in an FA Cup match since Theo Walcott nine years ago – as the Gunners ran out routine winners at Fratton Park.

Portsmouth took the lead after just three minutes, but Arsenal swiftly responded, and all of their goals came via set-pieces as Arteta's team once again demonstrated their prowess in such scenarios, while Noni Madueke also missed a penalty.

While Arteta was not happy with how his team started Sunday's contest, he was pleased with how they adapted after going behind. 

Holders Crystal Palace were dumped out by non-league Macclesfield on Saturday, and Arteta was determined to avoid any risk of a giant-killing.

"Part of the history of this competition means there is a lot to play for – to be in the next round but also a club’s reputation," he told TNT Sports. "You have to play with that mindset when you play at these grounds.

"We started exactly how we didn’t want to, giving them hope and momentum. But we managed to turn it around, and became more dominant. Positives to take, but some things to be better at.

"We were not at the level [early on]. When we adapted, Portsmouth suffered. We knew that they were going to give us a game and that is the beauty of this competition, that the margin becomes really close, especially when you give them momentum and a goal. We had to find ways to be dominant and adapt to margins.

"The second half was much better. We did react, and we did what we had to do. We are positive apart from the result because we made many changes."

Arteta rotated his squad, while he was also able to welcome Kai Havertz back into the fold following his return from injury.

"They know that they are all going to be important," the Spaniard said of how his fringe players react to not always featuring regularly.

"Everybody has a chance to play, everybody is involved. We’re going to need everybody’s contributions to achieve what we want."