Arsenal faced off with Sporting in the second of two Europa League ties on Thursday evening.
The score was locked at 2-2 after the first leg and the sides could not be separated after 120 minutes at the Emirates either.
Sporting went on to win 5-3 on penalties, knocking Arsenal out of the competition.
In a further blow, both William Saliba and Takehiro Tomiyasu picked up injuries from the game and Mikel Arteta has provided a less-than-positive update on the pair:
“Tomiyasu looks pretty serious from his reaction straight and what he said to me, but obviously, it’s very early,” the Spaniard said of Tomiyasu in his post-match press conference before going on to add: “Willy, I don’t know, he had some discomfort and could not continue so we had to take him out.”
Arsenal are in action vs Crystal Palace on Sunday, but both players could miss out, leaving Arsenal with very limited options at the back.
Should the Gunners win, though, they will go eight points clear ahead of the international break.