A first-half goal from Everton striker Shayne Lavery gave Northern Ireland Under 21s a 1-0 friendly win over Bulgaria in Spain.
Lavery, currently on loan to Falkirk, struck in the 18th minute to win the first of two challenge matches in Marbella for Ian Baraclough's side.
Northern Ireland will play Mexico on Monday in the second match of their week-long training camp.
The team is preparing for the Euro 2021 qualifiers which begin in September.
Friday's Bulgaria victory was a fourth win in a row for Baraclough's men, who kick off their campaign away to Malta, with Denmark, Romania, Ukraine and Finland also included in their group.
Northern Ireland only narrowly missed out on a play-off place in the previous Euros qualifying campaign, with a victory away to Spain their stand-out result.
With several of the players from that campaign now over-age, eight of Baraclough's 20-man panel for the Costa Del Sol trip have stepped up from the Under 19s.