Greece won on Tuesday a crucial battle in the two-year war to avoid a devastating default, securing a dual deal on a second bailout package and debt restructuring. But struggle continues, demanding the full implementation of commitments and focus on potential snags on the way to overcome the debt crisis that could throw global economy in deep recession.

During the latest eurozone's meeting in Brussels, after three-month deliberations with international state and private sector creditors, the Greek government received the "green light" to a 130-billion-euro (172.26 billion U.S. dollars) bailout loans package.

It is the second bailout to be granted to Athens since 2010, and in time to cover a bond repayment in March to avoid a chaotic financial collapse.

Tuesday's deal in parallel opens the way to ease the current total Greek debt loan of a total of 360 billion euros (477.04 billion dollars) by a third via a Private Sector Involvement (PSI) plan. The goal is to support the sustainability of the Greek debt by 2020 and the overall efforts to tackle the crisis.

Greek state officials, European politicians and some market analysts praised the agreement in the first reactions over the past few hours as a "life-line" that could resolve the country's urgent financial needs and avoid a catastrophic default with severe repercussions across the euro zone.

The agreement will allow breathing space to Greece for the implementation of the reform drive launched two years ago that could restore growth and offer a permanent solution to the country's problems, they explained.

But another part of Greek opposition parties, labor unionists and local and international commentators appeared extremely cautious to negative regarding the outcome, pointing to the "wrong elements" of the recipe and the potential snags on the way forward.

Greek analysts expressed a feeling of "deja vu". They reminded of a similar atmosphere of optimism after the first rescue loans package deal was clinched in May 2010 with EU and International Monetary Fund. Confidence was also voiced after the 26 October eurozone summit in 2011 that paved the way for Tuesday's agreement.

They noted that despite progress achieved since 2010 in the reduction of budget deficits, due to domestic reactions, increasing economic uncertainty across Europe and heavy recession linked to consecutive waves of austerity measures, Greece so far has not met all promises undertaken.

The country lags in particular in the structural reform part,deemed as a prerequisite to address the crisis and restore development in the long term.

The implementation of Tuesday's rescue agreement hides major challenges that could derail the entire project, according to local experts, such as Yorgos Kyrtsos, editor of Greek daily "City Press."

In coming days the agreement requires ratification by some euro-zone member countries. The process could turn out to become anything but an easy ride, since there is still skepticism amongst some European peers over Greece's commitment to swiftly and fully implement reforms.

But the biggest challenges lie in Greece as the government needs to push through a fresh set of harsh further austerity policies in the next few months, as they were pledged under the heavy pressure of lenders in exchange of the new aid.

Trade unions vowed culmination of "resistance to the slow death of Greek society," calling for a new round of protests and strikes starting from Wednesday over the unpopular belt-tightening measures that include 3.2 billion euro (4.24 billion dollars) worth further cuts on wages and pensions this year and mass dismissals of civil servants.

The unions said that the average Greek household already suffers an average 30 percent reduction on its annual income since 2009, warning that record high jobless rates of some 20 percent and unbearable disproportionate pressure on lower-middle class masses could fuel social upheaval.

Beyond the protesters on the streets, there is also threat of the vicious circle of austerity that fuels recession and vice versa.

It's already a reality. According to the latest official estimates, the Greek GDP shrank by 7 percent in 2011 and is due to decline by some 4 percent in 2012.

Unless the long-awaited parallel bold structural reform to boost economic growth starts unfolding, Greece will fail to meet debt reduction goals, noted analysts, Greek entrepreneurs, even the leaders of the two major parties that support the four-month old interim coalition administration of Prime Minister Lucas Papademos.

As Greece is expected to enter a pre-electoral period in March ahead of snap general elections due in April, political uncertainty could add up to the mix of challenges.

According to the latest opinion polls, no party will secure a solid parliamentary majority. A new coalition administration of conservative New Democracy and socialist PASOK which support the reform drive with a third party with reservations over the policy mix -- which is regarded as the most likely scenario by local analysts -- could be rattled by differences amongst partners.

But even incase of strong will by a new solid government to enforce the program, under the enhanced oversight by creditors, commentators express doubt over Greek society's strength to withstand the pressure and the sustainability of the plan.

They argue that despite impressive multi-billion euro figures and an over 50 percent "haircut" on the Greek state bonds held by private investors that deletes some 100 billion euros (132.51 billion dollars) of the Greek debt burden, Greece will probably need more assistance in the long run to be able to manage the crisis effectively.

Even if everything goes as planned, the country will be left with a significant debt loan in 2020 of 120 percent of GDP down from the current 160 percent, according to official figures. Greek analysts argue that the goal is wrong from the onset that it should be set out on a lower level to safeguard the sustainability of the debt.