Arsenal 3-1 Valencia: 5 things we learned

#3. Arsenal's defensive frailties continue to appear again

Diakhaby wheels away to celebrate his headed finish at the far post after some poor defending

After a week where they conceded three goals in three successive games, it's fair to say Arsenal's defensive frailties have returned to the fore. Nine goals conceded in three games. Over their last ten matches (all comps) prior to the 3-2 Crystal Palace defeat, they had only conceded six.

Yet the inconsistency at the back has reared its ugly head once more and Unai Emery can only watch as his side continue conceding preventable goalscoring opportunities which ultimately lead to silly goals. Whether they're individual mistakes, sloppy marking from set-pieces, poor decision-making or a combination of all three, the Gunners' defensively has been their Achilles heel for many seasons now and this one is no exception.

Shkodran Mustafi, playing against his former side on this occasion, made a few important interventions but equally performed like a man under pressure. Every time he was near the ball, you could hear the tension from home supporters - aware how his mistakes in particular have cost them crucial points in their top-four race this term.

As for Ainsley Maitland-Niles, he's playing out of position. Predominantly a winger or central midfielder, Hector Bellerín's long-term ACL injury means he has had to fill in and done a solid job at right-back - but not without the odd scare. Sokratis and captain Laurent Koscielny are regularly kept busy but are not without their faults, while the same can be said for Sead Kolasinac - a menace in transition on attacks but defensively suspect against top opposition.

Combine all of that and well, Valencia should've found themselves a three-goal cushion before the 20th-minute mark. Ezequiel Garay missed an open goal, Daniel Parejo forced Petr Cech into a save from distance while Mouctar Diakhaby's headed finish at the near post was painful to watch from a neutral perspective. Questions will continue to be asked of their defence and they're not being answered convincingly.