Glasgow City reached the Women's Champions League last 32 after beating Valur 4-3 on penalties in Reykjavik.
Leanne Crichton fired City ahead from close range in the second half after Jenna Clark had headed down Hayley Lauder's free-kick.
But Mist Edvardsdottir scrambled in an equaliser to force extra-time.
It took 12 spot-kicks in the shootout to separate the sides with Gunnhildur Jonsdottir firing wide after Zaneta Wyne converted for Glasgow.
"It just shows the spirit of the players," said head coach Scott Booth.
"The whole squad are so unified at the moment, all delighted for each other.
"In a one-off game, you just want to get over the line and we've managed to do that again.
"With this, we've had a great start to the season, the players are buzzing. Bring it on in terms of domestic football and let's see who we get in the last 32."
Iceland striker Hlin Eiriksdottir troubled the City defence early on after staying onside to latch on to a long ball, her eventual shot deflecting wide.
Glasgow settled into the game and threatened on 14 minutes when Kirsty Howat missed her kick with an attempted volley but got the break of the ball and drilled wide, with Nicole Robertson unable to make contact to divert the shot in.
And Robertson went very close when she met Wyne's superb cross from the left. When Howat did hit the target moments later, goalkeeper Sandra Siguroardottir was equal to the shot.
The half-time interval did not interrupt City's rhythm and Lauder's inswinging free-kick from the right was knocked down by Clark for Scotland midfielder Crichton to smash high past Siguroardottir.
Valur, who last year won their first Icelandic league title in nine years, needed a response but Asdis Karen Halldorsdottir could not get enough purchase on her header to trouble Lee Alexander and Jonsdottir sent a long-range shot narrowly wide.
Another effort from Crichton appeared to be blocked by an arm as City sought to put the game away but they would soon find themselves pegged back.
Elin Metta Jensen collided with Alexander as the goalkeeper attempted to clear and Halldorsdottir collected the loose ball before crossing to Hallbera Guony Gisladottir, whose header was hacked clear by Jo Love.
But when Gisladottir's corner was pushed out by Alexander, Edvardsdottir squeezed the ball over the line.
In extra-time, Jensen tested Alexander and Halldorsdottir's shot was deflected out but Glasgow prevailed in the shootout to make it 10 Champions League last-32 appearances in a row.