Neil Warnock has admitted that Swansea striker Bafetimbi Gomis could hand Dwight Gayle a Crystal Palace lifeline
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Portugal striker Nelson Oliveira will join Swansea City until the end of the season on January 1.
Oliveira, who has won 14 caps for his country and played for Portugal at Euro 2012, joins from Benfica where he has struggled to make an impact since first breaking into the first-team as a teenager.
The 23-year-old's arrival solves a problem for Swansea manager Garry Monk who will lose top scorer Wilfried Bony to the African Nations Cup next month.
Ivory Coast striker Bony could miss up to six games in January and February and Bafetimbi Gomis is the only other recognised senior striker in the squad.
"I'm really looking forward to it,'' Oliveira told Swansea's official website.
"I already know quite a bit about Swansea and it was their style of play and the ambience at the club that attracted me. It was an easy decision to make.
"The deal was agreed early so I can spend an extra 10 days in Swansea training with the squad and getting to know my new team-mates."
Wales international rugby union player Liam Williams apologised after he posted a photo on Twitter of himself 'blacked up' as Swansea City forward Wilfried Bony.
Williams appeared alongside three team-mates in fancy dress, in full Swansea kit and with his face 'blacked up'.
Campaign group Show Racism the Red Card said it was "disappointed to see the image".
I am very sorry for any offence caused by my actions. I'm not a racist and there was no malice behind it.