Arsenal manager Arsene Wenger lauded Francis Coquelin and believes the midfielder is playing like a big-money signing.
Coquelin, 24, was on loan at Charlton before being recalled by Arsenal in December last year – leading to several tenacious displays in midfield.
Such were his performances, Coquelin re-signed with the club in February.
Wenger believes the Frenchman is yet to receive the plaudits he deserves, mainly because big-money signings get more credit.
"The world has changed," Wenger said.
"The appreciation today of the quality of a player is just down to the money you spend. If we had bought Coquelin at Christmas for £40million, everyone would say, 'What a signing'. I am sorry he didn't cost any money. He is still a good player."
Arsenal are third in the Premier League ahead of Wednesday's clash at home to relegation-threatened Sunderland.
Wenger's priorities in the transfer market are believed to be a goalkeeper and defensive midfielder, and he said his approach would remain unchanged despite Coquelin's emergence.
"It hasn't changed a lot," Wenger said.
"What is for sure is Coquelin has shown he has the capacity to play for us and play a big part in the success of the team.
"I think nobody would dispute that his performances have been convincing and that he is ready for a fight - even if somebody comes in. Even if somebody else comes in, he will stay here. I extended his contract. That means I believe in him."
