Kieran Tierney has had tests on his shoulder after he was forced off through injury in Arsenal's 3-1 win over West Ham .
The Gunners finally ended a nine-match winless run as Freddie Ljungberg got off the mark three games into his interim reign.
But the victory came at a price for Arsenal , as an injury in the warm-up for right-back Hector Bellerin was followed by a blow for fellow defender Tierney less than half an hour into the game.
Tierney was seen coming out of the dressing room at the London Stadium with his arm in a sling, and was taken to hospital for tests on his shoulder, according to Football London journalist James Benge.
The Scottish left-back had fallen awkwardly in his own box and immediately gestured to the touchline that he had damaged his shoulder when landing.
He received on-pitch treatment, but had to make way for Sead Kolasinac, who only came into the squad after Ainsley Maitland-Niles was called up to start in place of the injured Bellerin.
The injuries marred what was a welcome win for Arsenal, with Nicolas Pepe inspiring a sensational comeback after Angelo Ogbonna had given West Ham the lead.
Brazilian youngster Gabriel Martinelli equalised on his first Premier League start - becoming the youngster player in the club's history to score on his first top-flight appearance.
Arsenal then took the lead through Nicolas Pepe before Pierre-Emerick Aubameyang secured the points moments later.
Tierney signed for Arsenal from Celtic in the summer but missed the start of the season with a hip injury, eventually making his debut in the 5-0 Carabao Cup victory over Nottingham Forest in September.
Bellerin only returned to action in October following an ACL injury which kept him out for most of the previous campaign.
