Liverpool have signed Athletic Bilbao teenage defender Mikel San Jose for a reported fee of £270,000 in less than 24 hours after capturing Bulgaria U-21 goalkeeper Nikolay Mikhailov.

The 18-year-old central defender had impressed in the junior sides of the Basque outfit and was touted to make it to the first team sooner than later. However, Bilbao have expressed helplessness on San Jose leaving for Anfield, saying it was not possible for them to fight “a European giant.”

"For us it is bad news, but Mikel has decided on the choice of Liverpool and it was impossible for us to fight against a European giant," Athletic Bilbao said in a statement.

San Jose said: "It was a surprise for me but I have decided to accept the chance at Liverpool. I am very excited but now I know that I have to work more each day to get in the first team."

The Reds had earlier signed teenage Hungarian strike duo Krisztian Nemeth, 18, and 17-year-old Andras Simon, who are expected to play in the reserves; while Mikhailov, 18, is said to be a replacement for veteran keeper Jerzy Dudek, who will be leaving as a free agent.