Inter Milan defender Cristian Chivu - a reported target for Liverpool - is a 'serious option' for Ajax, according to Frank De Boer.
The 31-year-old is seemingly likely to leave the San Siro in January as Inter look to cash-in before his contract expires in the summer.
Liverpool have been credited with interest in Chivu, with Kenny Dalglish reported to be keen to bolster his defensive ranks at Anfield.
But, it would appear, the Reds will have to contest Ajax in pursuit of the Romania international, who was also considered by De Boer in the summer.
The Godenzonen boss had identified Chivu as a possible replacement for Jan Vertonghen, who had reportedly been attracting interest from the likes of Liverpool and Arsenal.
And, even though Vertonghen remained at the Amsterdam Arena, Chivu could yet move to Holland during the winter transfer window.
"He is certainly a serious option", said De Boer.
"Last summer we thought of him as a possible replacement for [Jan] Vertonghen, who at that time was attracting much interest.
"Joris Mathijsen was also a potential replacement for Jan, but he chose Malaga.
"Then our eyes fell on Cristian."