Chelsea have completed the signing of Guinea-born striker Thierno Ballo,less than 48 hours into January transfer widow.

Ballo, who was born and raised in Austria, signed on scholarship with the Blues yesterday after leaving German side Viktoria Koln.

“We narrowed down a few clubs and looked closely at not just the infrastructure but also the training work, so Chelsea made the best impression,” said his former club chairman,Peter Huemerlehner.

“So far, the press reports and praise have never influenced him. He is very focussed on himself; what is written has not reached him so far.”

The 16-year-old is regarded as one of the brightest young prospects in Europe and has scored seven goals in 25 league appearances for the club’s Under-17 side.

He began his career with SC Chemie Linz before joining Koln where he netted over 200 goals in two years at the club.

Ballo, made his debut for Austria’s Under-17 side when he was just 14 years old and has scored seven goals in 22 games at international youth level.