LONDON -- The double injury blow of losing Kieran Tierney and Thomas Partey was always going to ask some difficult questions of Arsenal manager Mikel Arteta, but he has to come up with a better answer than this.
Brighton -- a clever but out-of-form team with one goal in seven games, six of which they lost -- deserved their 2-1 win here at Emirates Stadium on Saturday as goals from Leandro Trossard and Enock Mwepu dealt a huge blow to the Gunners' hopes of securing a Premier League top four finish.
Arsenal have surrendered the initiative in the race for Champions League qualification with two defeats in six days -- and Arteta compounded the absence of two key players with a team selection Saturday that only contributed to a disjointed display.
Deploying midfielder Granit Xhaka at left-back to replace Tierney was a mistake. Xhaka has deputised in that position before but with Partey already absent, losing the Switzerland international's range of passing in midfield only served to heighten the disconnect throughout the team.
Albert Sambi Lokonga, in his first start since Jan. 23, was asked to anchor a three-man midfield, providing defensive cover while enabling Arsenal to play out from the back. The difficulty of that task was exacerbated by Xhaka's absence from the same area of the pitch, something Arteta sought to rectify in the second half by encouraging Xhaka to drift into midfield when the home side were in possession.
Although there was a late rally from Arsenal, triggered by Martin Odegaard's deflected long-range strike halving the deficit with 89 minutes played, this performance was a bit of a mess, far from the structure and rhythm they have played with at their best under Arteta.
They did have their moments. Gabriel hit the side-netting with a close-range header before Trossard's opener and Gabriel Martinelli had an equaliser disallowed on the stroke of halftime for offside. After Mwebu doubled the visitors lead with a superb goal featuring lovely link-up play between Trossard and Moises Caicedo, Odegaard hit the crossbar with a free-kick and substitute Eddie Nketiah achieved the same with the rebound.
But there was a lack of cohesion and balance to Arsenal, which only underlines the difficulty they now face with such a small squad in offsetting the absences of Tierney, who underwent knee surgery on Thursday, and Partey due to a thigh problem.
"With all of the team available, we know how difficult the challenge that we have ahead," said Arteta. "With those two big injuries it makes the situation more complicated. We cannot look at that because we are going to be looking for excuses, and what happened today is down to us with the players we have and the way we have prepared for the game."
By hauling off Nuno Tavares at halftime against Crystal Palace, Arteta will have put more doubts in the mind of the most logical understudy to Tierney. Tavares was an unused substitute here but surely he will be called upon at some stage as his inclusion would allow Xhaka to return to his natural midfield role.
Cedric Soares could also be deployed at left-back once Takehiro Tomiyasu is fit again but the Japan international will not return to full training following a calf problem until after next weekend's game at Southampton. Finding a way of returning Xhaka to the heart of the team feels imperative after Saturday's display. The cushion Arsenal had in the top four race has gone and Arteta did not hide from the difficult moment they now find themselves in.
"What happens [now] is criticise ourselves a lot," he said. "Get slapped again because we deserve it, because we were really poor again the first half, and lift ourselves up because we know that this road is taking us nowhere -- especially where we want to be.
"We have everything to play for in the last eight games. We have to have that level of energy and visualise the challenge -- the beautiful challenge we have ahead and don't sit back and see what happens."
Alexandre Lacazette was a peripheral figure once again, now without a goal from open play since December 11. He touched the ball just 21 times -- the fewest of any starter -- and attempted just eight passes. His individual xG was 0.00. The only other Arsenal outfield player with the same blank was Ben White, who found himself the subject of much derision from the away fans having left Brighton in a £50 million move last summer.
Nketiah and Nicolas Pepe tried to make an impact off the bench as they have done previously, but the lack of options Arteta has at his disposal after streamlining the squad in January comes into sharper focus on days like this.
Arsenal have shown they can overcome adversity this season. But the dual loss of Tierney and Partey feels one of their biggest hurdles yet.