Arsenal endured a nightmare start to their clash against Liverpool as William Saliba was forced off with an injury.
With less than five minutes played at Anfield, the centre-back went down on the turf and it quickly became clear he couldn't continue.
Saliba appeared to hurt himself with just minutes on the clock
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Saliba appeared to hurt himself with just minutes on the clockCredit: Getty
It's unclear what the actual injury is, although he went down after a collision with Reds forward Hugo Ekitike.
Cristhian Mosquera was the man to replace Saliba in the back line.
Saliba could join Bukayo Saka, Kai Havertz and Gabriel Jesus as the latest absentee for Arsenal.
"I saw the incident actually," talkSPORT's chief football correspondent Alex Crook said live on air.
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"He came over to this near touchline, right in front of the Arsenal dugout to make a clearance and he pulled up awkwardly after that clearance and went down a couple of minutes later.
"Arsenal took no chances. Christian Mosquera, one of their summer signings, immediately sent on in his place. It looks like another muscular problem.
"We've seen a few of those already in these early weeks of the season. No Saka for Arsenal this afternoon.
"Martin Odegaard, their captain, fit enough only for a place on the bench. And, well, it's a big game, isn't it, for Mosquera to come into."
Arsenal legend Perry Groves added: "Huge setback. It looks muscular.
"Then you just hope that it's not going to be too serious. But it's a big, big test for Mosquera.
Saliba departed the field of play early on at Anfield
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Saliba departed the field of play early on at AnfieldCredit: Getty
"Obviously, Gabriel, who's the captain today for Arsenal, he's got to take responsibility. Young Mosquera needs talking through the game.
"So, yeah, it's a huge, huge blow for Arsenal. But you get these in the season.
"Now it will be a test of how strong and how deep the squad is."
How Arsenal could respond to Saliba injury
Saliba will undoubtedly be a huge miss for Arsenal given the strong partnership he has with fellow centre-back Gabriel.
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However, the Gunners signed Mosquera as defensive cover earlier in the summer.
And talkSPORT previously reported their interest in Piero Hincapie of Bayer Leverkusen.
It remains to be seen how long Saliba will be out for
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It remains to be seen how long Saliba will be out forCredit: Getty