I think that Iva should get by Daniela Casanova fairly routinely, but I am not so sure that Denisa will be that easy for her- they have only played once surprisingly:
Iva MAJOLI (CRO) v Denisa CHLADKOVA (CZE)
2002 Vienna Clay (O) 32 Iva MAJOLI 5-7 6-2 6-4
Iva MAJOLI (CRO) leads 1 : 0
Pretty tough and that was on clay, Iva's best surface!
Ondraskova has also had a few decent results, beating Matevzic and Antonella Serra-Zanetti, but I expect Denisa to win this one.
Iva has only played Srebotnik once too, earlier this year at the US Open where Iva won 6-4 6-4. That one was close too. Get through these matches IVA!!!! I think Denisa will be a real test for her, but hopefully she can pull this one off and then get by Katarina too. Jana Kandarr can play some good tennis too, but has been so inconsistent this year. She might surprise Katarina, but I doubt it.