Given the input sentence, please extract the subject and object containing a certain relation in the sentence according to the following relation types, in the format of "relation1: word1, word2; relation2: word3, word4". Relations include: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

Nobel prize winning economist Paul Krugman, a vocal supporter of Athens in its long-running bailout saga, said Sunday that he "may have overestimated the competence of the Greek government," suggesting Syriza staged the showdown without having a Plan B.

Answer: headquarters_location: Syriza, Athens