Wolverhampton Wanderers striker Raul Jimenez is reported to be conscious and responding to treatment in hospital after a sickening clash of heads with Arsenal defender David Luiz.
The incident happened in the 16th minute of Sunday's Premier League match at the Emirates Stadium. Jimenez and Luiz were both injured in an aerial challenge following an Arsenal corner - but the Wolves man came off worse.
Luiz was visibly concerned for his opponent but able to continue after receiving treatment and having his head bandaged.
However, after a 10-minute delay in play, the stricken Jimenez had to be carried off on a stretcher and was seen receiving oxygen. The Mexico international was subsequently taken straight to hospital.
Wolves said on their official Twitter account: "Raul Jimenez is stretchered from the field after he and David Luiz clash heads inside the Wolves box. Fabio Silva comes on in his place.
"We will bring you more information on Raul as soon as we have it."
Arsenal responded to the incident by tweeting: "Sending strength and best wishes to Raul."
And Gunners forward Mesut Ozil - not involved in the match - also took to Twitter to say: "Get well soon, Raul Jimenez! Hope you have a speedy recovery."
Wolves went on to open the scoring through Pedro Neto in the 29th minute.
Arsenal levelled a couple of minutes later courtesy of a Gabriel header, only for Daniel Podence to put the visitors back in front before half-time.
In the second half, Sky Sports reported that Jimenez was "conscious in hospital and responding to treatment".
