A second-half winner from Arkadiusz Milik steered Poland to a 1-0 victory in Euro 2016 Group C on Sunday as Northern Ireland's first appearance at a major finals for 30 years ended in disappointment.
Making their debut in the competition, the Irish were unable to cope with an attacking Polish outfit that dominated most of the opening match of the group to clinch their first win in three appearances in the finals.
After a goalless first half, a Jakub Blaszczykowski cross found Milik in the penalty area in the 51st minute and the forward blasted his left-foot shot through defender Craig Cathcart's legs and into the net.
It was Northern Ireland's first game at a major finals since they lost 3-0 to Brazil at the 1986 World Cup in Mexico, exactly 30 years ago to the day.
Despite a late rally from the industrious Irish, Poland never looked likely to lose.
"We gave it our all but it was not good enough," Irish captain Steven Davis said. "It's a learning curve for us and hopefully we can learn from it."
Poland, who had failed to win their previous six games at European Championship finals, dominated the first half but were unable to turn the pressure into goals.
They had a chance to go ahead after 32 minutes when Milik found himself unmarked on the left of the box but his left-foot shot flew over the bar.
Seven minutes later a fierce drive from Bartosz Kapustka from just inside the penalty area forced goalkeeper Michael McGovern to make a superb save.
The Poles were rewarded for their industry six minutes into the second half when Milik took one touch from the cross and fired home.
The goal helped them to relax while the Irish were forced to play more attacking football.
Substitute Conor Washington forced Poland goalkeeper Wojciech Szczesny to race off his line to save in the 72nd minute.
The Irish, however, did not create enough chances to earn a draw and now need a better result against Ukraine in Lyon on Thursday to have a chance of reaching the last 16.