Michu has scored 10 goals in 15 Premier League games for Swansea and team-mate Angel Rangel believes the South Wales club must resist the temptation to sell.
"That's something the club has to consider and he is a player we can't afford to lose," said Rangel after Michu's two goals beat Arsenal.
"Hopefully he will stay here for a long time and we can have good success."
"That's a massive achievement," said Rangel, one of Swansea's four-strong Spanish contingent.
"Not many players can score 10 goals in the Premier League. He has done a fantastic job. He gives us an aerial threat that we probably lacked a bit before.
"He is feeling comfortable, enjoying his life in Swansea and everyone is happy with him."