Blues have the edge
Linfield struck twice in the second half to earn a 2-0 win over NSI Runavik in the first leg of their Europa League first qualifying round tie.
Captain Andy Waterworth put last season's Danske Bank Premiership runners-up ahead in the 57th minute and Guy Bates added a second in the 73rd minute to leave Linfield in a healthy position heading to the Faroe Islands.
It is not looking so good for two of Northern Ireland's other representatives though, with Glentoran and Glenavon both suffering home defeats.
Cup-winners Glentoran were beaten 4-1 by MSK Zilina of Slovakia, for whom Matej Jelic (13), Jakub Paur (20), Lukas Cmelik (59) and Ernest Mabouka (81) struck the goals. Conor McMenamin got Glentoran on the scoresheet, but they face a huge task to get through.
Glenavon also have work to do, but not as much as Glentoran, as they were beaten 2-1 by Belarus side Shakhtyor Soligorsk. It looked set to be a bad night for the hosts at Mourneview Park when Mikhail Afanasiev and Dmitri Komarovski put the visitors 2-0 up inside 30 minutes, but Mark Patton's 86th-minute strike has given Glenavon a lifeline.
In-form SSE Airtricity League Premier Division side St Patrick's were unable to extend their five-match domestic winning streak as they lost 2-1 at Skonto Riga.
Saints took a 21st-minute lead through Aaron Greene's fine volley but the visitors failed to make the most of their chances and ended up paying the price as Skonto snatched victory with goals from Arturs Karasausks (38) and Vladislavs Gutkovskis (65).
Cork City were held 1-1 at home by Icelandic side KR Reykjavik, captain Alan Bennett's 19th-minute strike being cancelled out by Oskar Orn Hauksson nine minutes later, but University College Dublin did manage to claim a victory.
UCD, who play in the Airtricity League first division after being relegated from the Premier Division at the end of the 2014 season, were handed a place in the competition when the Republic of Ireland was granted an extra berth for its third place in UEFA's Fair Play League.
And they got off to a winning start as Ryan Swan's goal on the stroke of half-time earned them a 1-0 home triumph over Luxembourg club Dudelange.
There were mixed results for the three Welsh clubs in action, with Newtown picking up a win but Airbus UK and Bala both losing.
Bala were beaten 3-1 away by Differdange, although it could have been even worse for the Welsh Premier runners-up as they found themselves trailing 3-0 inside 26 minutes through goals from Omar Er Rafik, Gauthier Caron and Dejvid Sinani before Ian Sheridan pulled a goal back before the break .
Broughton also suffered a 3-1 loss. They took a 28th-minute lead at home to Lokomotiva Zagreb through Wayne Riley but then conceded goals to Damir Sovsic (48), Mirko Maric (61) and substitute Marko Kolar (68) and only prevented a fourth thanks to goalkeeper James Coates, who saved a late penalty from Sovsic.
It was a better night for Newtown, for whom Jason Oswell scored a stoppage-time winner to give them a 2-1 lead to take to Maltese side Valletta.
Luke Boundford's 40th-minute opener was cancelled out by Jhonnattann midway through the second half but Valletta lost captain Ian Azzopardi to a red card with five minutes to go, and Newtown capitalised through Oswell.