An 87th-minute Andy Waterworth goal gave Linfield a deserved Europa League first leg win over Swedish side AIK Stockholm at Mourneview Park.
The substitute latched onto a ball over the top and kept his cool to slot home past goalkeeper Patrick Carlgren.
Minutes earlier Sean Ward had forced Calgren into an outstanding save from his 22-yard first-time volley which looked destined for the top corner.
Nabil Bahoui drilled a low shot against the base of the post for the visitors.
The Blues started their 100th game in European competition brightly and Stephen Lowry steered a header from a Michael Carvill cross a couple of yards over the bar.
The impressive Carvill then had a shot blocked inside the box and saw his low shot from the edge of the box easily gathered by Carlgren.
Anton Jonsson swept a left-foot shot wide of the target from 25 yards and Henok Goitom also fired wide after bringing the ball down brilliantly following a Nils-Eric Johansson pass.
Carvill's neat pass set up Peter Thompson, but the striker's shot from the edge of the box cleared Carlgren's crossbar.
Two minutes into added time at the end of the first half, Kennedy Igboananike shot just wide from 23 yards.
After the break, Lowry shot over after Carvill's lay-off and then Bahoui beat the offside trap before hitting the woodwork, Igboananike blasting the rebound over.
The sides meet again in Sweden next week, with the tie very much alive.
Linfield striker Andrew Waterworth:
"The boys who started the game were very disciplined and it was nice to come on and make an impact as a substitute.
"We know it will be tough in Sweden but we will go there determined to defend our one-goal lead."