Celtic teenager Watt agrees new deal
"I'm delighted to have signed this new contract," he said. "I'm a Celtic fan and this is where I want to play my football.
"The last couple of weeks have been incredible, and to sign the contract just a week after scoring against Barcelona is brilliant.
"I know I've still got a lot of hard work ahead of me in my career, but it's great to know that I'll be here as part of this exciting young team the manager is building at Celtic."