Salesforce workflow rules dont fire up for leads created by Marketo

I have some workflow rules in Salesforce which assign an owner and a region for a new lead based on its country. The rules are set to fire once the new lead is created.
When new leads are coming in Salesforce from Marketo, all the lead info (including country) is in place, but the new owner an region dont appear. 
Maybe that's because when Marketo creates a new user in SF via sync, it first creates the new lead (name, company, status) and after that appends the related info (such as country)? So at the timeof creation the lead doesnt contain the country, so the SF workflow rule won't fire up...

Thanks,