Valur manager Arnar Gretarsson has admitted St Mirren should have scored twice in the first-half in Reykjavik.
The Icelandic boss, 52, was relieved to see his side make half-time with the scoreline level but insists Valur could have been ahead themselves but for Ellery Balcombe between the posts.
The St Mirren goalkeeper - on loan from Brentford - sprung into action to deny Valur on a handful of occasions with top-notch stops to ensure the tie remains level heading back to Paisley next week.
Reflecting on the stalemate, Gretarsson said: "It was what I expected. I think maybe it was a fair result, I don't know. I think it is an open game for the second leg, I think we have a chance there.
"It is going to be more difficult definitely as they will have a full stadium.
"St Mirren had a lot of chances, especially in the first half. They should have scored two goals.
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"We made a couple of mistakes in the first half which we were lucky not to concede goals.
"When I say that, it was us making mistakes it's not that they were playing through us.
"When you have the opportunities you need to be clinical.
"The goalkeeper was very good. I thought we created enough to score one or two goals, I thought their goalkeeper made a few excellent saves."
Buddies boss Stephen Robinson also hailed his goalkeeper for his important saves in the big moments.
"We created a lot of chances," he said. "But Ellery made two super saves and he deserves a lot of credit.
"His distribution was very good too."
