Tsakalotos, a low-key Oxford University-trained Marxist economist, was at the finance helm when Greece and its creditors produced an 86 billion-euro loan accord on August.
Chouliarakis, who was finance minister in the caretaker government during the recent election campaign, was a senior member of the bailout negotiation team, known for his grasp of details.
The appointments, which came as Tsipras appointed a mostly unchanged new Cabinet following re-election on Sunday, come ahead of a review by lenders starting next month on progress in meeting bailout targets, recapitalizing the country`s banks and holding discussions that Greece wants on debt relief.
"The markets will see this positively," said Takis Zamanis, chief trader at Beta Securities in Athens. "It appeared the chemistry was right between Tsakalotos and lenders."
Tsakalotos is a stark contrast to his combative predecessor Yanis Varoufakis, who quit Tsipras`s government in disagreement over the bailout in July. Varoufakis frequently riled lenders with outspoken and occasionally undiplomatic remarks, including one where he said he wore `creditors` loathing with pride`.
Dutch-born and British-educated Tsakalotos, however, is a member of the so called `53+` faction in Tsipras` leftist Syriza party, some of whose members recently expressed concerns the party was moving away from core leftist values to hold on to power.
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