Chelsea's pursuit of Atletico Madrid star Sergio Aguero is set to go to the wire in this summer's market.

The Mail on Sunday says though the club are keen to deliver a star signing for new manager Carlo Ancelotti - with the best will in the world, Yuri Zhirkov does not fit the bill - Atletico's asking price has been £50million and despite reports in Spain, no new bid is on the table.

The Argentine striker did impress in front of Chelsea owner Roman Abramovich in his country's 3-2 win over Russia in Moscow but this could go down to the deadline.

Atletico have a dilemma ahead of Wednesday's Champions League qualifier against Panathinaikos: if they play him, he is ineligible for the tournament. If they leave him out, they risk missing the group stages.