It's advantage Dundalk after the first leg of their Europa League First Round Qualifier.
Dylan Connolly was on target as the SSE Airtricity League leaders picked up a 1-0 victory at Estonia's Levadia Tallinn.
However, Shamrock Rovers and Derry City both face uphill tasks to qualify.
Daniel Sundgren scored the winner as AIK Stockholm beat Rovers 1-0 at Tallaght Stadium.
Derry City lost 2-0 to Dinamo Minsk at the Brandywell, with goals in either half from Nino Galovic and Vladimir Khvaschinski.
Candystripes' midfielder Conor McDermott was sent off after receiving a second yellow card late on.