Arsenal were put in the strange position of being allowed to use four substitutes in the Premier League game against Newcastle.
That was down to the Premier League's concussion rule, with Newcastle defender Fabian Schar being forced off early in the second half due to a head injury. As a result, both teams were then allowed to use four substitutes in the match at St. James' Park.
It was a decision that Mikel Arteta did end up coming to, with Takehiro Tomiyasu suffering an untimely injury right before half-time. The Japanese full-back went down clutching his hamstring before being replaced by Cedric Soares.
READ MORE: Arsenal handed major injury blow as Takehiro Tomiyasu forced off vs Newcastle
Following the injury to Schar early in the second half, Arteta then elected to use his second substitute of the game as Gabriel Martinelli replaced Emile Smith Rowe with 53 minutes on the board. But just two minutes later, Newcastle took the lead through a Benjamin White own goal.
Alexandre Lacazette was then introduced just after the hour mark, but suffered an injury of his own as his head was bloodied not too long after replacing Nuno Tavares. However, the striker stayed on after receiving medical attention.
Arteta used his unexpected last roll of the dice to introduce club-record signing Nicolas Pepe from the bench with Gabriel Magalhaes making way. However, the change did not have the intended effect, with the Gunners suffering an onslaught from Newcastle that eventually led to a second goal for former Gunners target Bruno Guimaraes.
