Viergever leaves it late for AZ
Nick Viergever's 89th-minute goal gave AZ Alkmaar a 1-0 first-leg advantage in their Europa League last-32 tie with Slovan Liberec at the Stadion U Nisy.
AZ dominated but struggled to break down their opponents before Viergever took advantage of a goalkeeping error to give the away side the lead going into the second leg.
If Dick Advocaat's side can avoid defeat at home next week they could set up a chance of revenge against Anzhi Makhachkala, who beat them 6-0 on aggregate in last year's competition.
A subdued first half produced few chances, with only AZ's Celso Ortiz and Roy Beerens testing goalkeeper Premysl Kovar with shots from range, while Johann Berg Gudmundsson had an effort from the edge of the area blocked by Jan Rajnoch.
Nemanja Gudelj and Jeffrey Gouweleeuw both had efforts caught by Kovar in the second half but in truth the Czech keeper was not troubled.
Liberec had the game's best chance so far with 16 minutes left to play as AZ keeper Esteban was forced to tip away Yevhen Budink's right-footed shot for a corner.
But with time running out Gudelj's free-kick from deep was parried by Kovar, allowing centre-back Viergever to pounce on his mistake and prod into the unguarded goal from six yards out to finally break the deadlock.
Liberec rallied in search of an equaliser but Sergiy Rybalka's shot flew wastefully over the bar, leaving AZ and their supporters to celebrate a narrow victory and a great chance of advancing to the next round.