Dortmund snap up Swedish teenage striker Isak

BERLIN (Reuters) - Borussia Dortmund have signed Swedish teenager Alexander Isak on a long-term contract pending a green light from world soccer's governing body FIFA due to the gifted striker being under 18, the German club said on Monday. Dortmund also said they had extended the contract of U.S. international Christian Pulisic, with the hugely talented 18-year-old attacking midfielder penning a deal to 2020. The 17-year-old Isak, who only days ago he was reportedly set to join Spanish giants Real Madrid, made his professional debut for AIK at the age of 16. He became Sweden's youngest ever goalscorer this month, netting in his first start in a 6-0 friendly thrashing of Slovakia. "He is an amazing striker talent sought after by many top European clubs," Dortmund sports director Michael Zorc said. "We are delighted that he decided to join Borussia Dortmund." "Dortmund and the player are both convinced this is a transfer with great prospects." Isak is widely regarded as the most promising Swedish player since Manchester United striker Zlatan Ibrahimovic. Technically excellent, the slight teenager's greatest strength is his maturity and ability to make the right decisions under pressure. Isak scored 10 league goals in 19 league starts to help AIK finish second in Sweden's top flight last season and qualify for the Europa League. Pulisic joined Dortmund in 2015 and has been outstanding since, earning 11 caps for the United States since his first call-up in 2016. "I still have a lot to learn," he said. "I have the best conditions for that here in Dortmund and I have the chance to play in front of 80,0000 fans. It cannot be better." (Reporting by Karolos Grohmann, editing by Ed Osmond)