The Gunners now have the worst defence of the top six sides and are yet to keep a clean sheet away from home following their 2-1 win over Huddersfield on Saturday.
The troubled Terriers spent most of the game on the front foot but all they had to show for their efforts was an injury-time Sead Kolasinac own goal.
Insisting that a top-four finish was a realistic target, the Spaniard said: "I think it's hard, but we can (finish in the top four)".
And he will be encouraged by the fact Arsenal have won all three of their Premier League meetings with Huddersfield.
"Knowing we need to take the regularity at home and away, and today this victory I think can give us confidence and the possibility to continue our target in the Premier League". Our motivation is very great and every player wants to, in every match, and have regularity and consistency in the Premier League in 38 matches. "The clean sheet is important but we can get a clean-sheet (sometimes) and draw".
A Nigerian professional footballer, Alex Iwobi, who plays as a forward for Arsenal, contributed to the sinking of Huddersfield in Saturday's encounter.
"At the moment there is one point difference between United and us".
Against Huddersfield, the league's bottom side who had not scored a goal in eight hours and 27 minutes before Saturday, Arsenal, even with a two-goal advantage, never looked comfortable and with better finishing the hosts would have made a game of it.
Pleased to have returned and ready to help the team, the 3-year-old added: "Yes, I was happy to be back after two months and I was excited".