Hornets youngster Josh Doherty helped Northern Ireland clinch their fourth Milk Cup Elite Section title after a 1-0 win against Canada.
The 18-year-old, who made his Watford debut as a second-half substitute against Huddersfield Town on the final day of last season, started the clash.
A cagey first period was followed by a more open second half. Northern Ireland had several chances but it was a penalty from Aaron McEneff which secured a narrow victory for the hosts.
The victory meant Northern Ireland finished their Milk Cup campaign with a 100 per cent record after wins against China, Mexico and Canada.