Chelsea goalkeeper Emiliano Martinez has been rushed to hospital after a sickening collision with Everton defender Jarrad Branthwaite.
The players clashed heads as Martinez came off his line to collect a cross into the Everton box, with Branthwaite attempting to attack the ball.
There was immediate concern for both players as they stayed down in the box, but Branthwaite was able to return to his feet after a couple of minutes.
Martinez, however, stayed down on his back as Chelsea physios and medical staff worked with caution and the stretcher was called.
The Argentinian received oxygen on the pitch and was eventually carried off to pitch on a stretcher around 10 minutes after the collision.
Broadcaster TNT Sports, who decided against showing a close-up replay of the gruesome clash of heads, reported that Martinez was immediately taken to hospital.
But the goalkeeper appeared to be conscious and was moving his arms while he was stretchered straight down the tunnel, in what appeared to be a positive sign.
Martinez was replaced in the 73rd minute by Belgian reserve goalkeeper Mike Penders, who came on to make his Premier League debut with Chelsea leading 1-0.
Branthwaite was cleared to continue for Everton after team physios performed concussion checks on the pitch.
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