(Bloomberg Opinion) — By winning the Rugby World Cup final against England on Saturday, South Africa became only the second country to secure three cup titles. In upsetting a heavily favored English team, it also achieved the unlikely accomplishment of winning every World Cup final in which it has appeared. All of that not only places South Africa among rugby’s elite nations, it also gives the country a golden opportunity to unite to address deep and growing economic, financial and social challenges. Moreover, the country’s victory not only inspires us, it provides an important lesson about succeeding in conditions of potential adversity.South Africa went into the final in Japan as underdogs against an England team that shone in the semifinals against the legendary New Zealand All Blacks. Understanding the enormous challenge it faced, the team adjusted its approach and did so successfully. South Africa deployed brute force that dominated the English in set pieces, stifling and frustrating its opponent in the first half and opening the way for the exceptional scores that crushed England in the second. The result was a convincing 32-12 victory.The ability to adjust to beat a stronger opponent was also evident when South Africa won its first World Cup in 1995 against New Zealand. It was similar in another way, too, providing inspiration reminiscent of when Nelson Mandela — the former freedom fighter, longtime prisoner of the previous regime and recently elected president of a country trying to “forgive but not forget” the terrible period of apartheid — wore the shirt of a sport and team that had been particularly cruel to all but the white South Africans. It was a historic moment that fueled the vision of a “rainbow nation.”This time around, the team was led by Siya Kolisi, the first black player to captain a South African rugby squad. Kolisi had grown up in the poor township of Zwide and was watched during the match by his visiting father, who had never flown on a plane before. Referring to how he had pulled himself out of extreme poverty and deprivation, he pointedly said after the game: “Growing up, I never dreamed of a day like this at all. When I was a kid, all I was thinking about was getting my next meal.”That is just one reason Saturday’s victory goes well beyond making rugby history. It provides the country with the opportunity for an important and timely unifier to confront serious and deepening problems of poverty, marginalization and potential financial instability.This inspiring moment in sports also carries important lessons for governments, companies and households dealing with realities that, only a few years ago, would have been deemed unthinkable: $15 trillion of negative-yielding bonds, QE infinity in Europe, the transformation of the U.S. from a champion of liberalization and free trade into a supporter of protectionism, to name but three of a long and lengthening list. It shows how a combination of resilience, optionality and agility can help successfully navigate a worrisome and cloudy outlook.This is the combination that economic entities need to navigate today’s unusually uncertain world:Resilience — Anchored by strong balance sheets, few debt maturity and currency mismatches and high cash flow and reserves, it allows them to stay in the game even if they make a mistake, just as South Africa did with its reliance on strong play. Optionality — Anchored by forward-looking scenario analysis, creative thinking and more open-minded operating approaches, it allows them to evolve their reasoning and make mid-course adjustments as facts and signals becoming clearer, like the smart half-time adjustments by South Africa. Agility — It allows them to strike when opportunities arise, similar to the two tries that South Africa scored out of nowhere in the second half that deflated England for good.Whether they realize it or not, a growing number of countries, companies and individuals risk being turned into underdogs by developments they cannot control in the global economy. To win in such an environment, they need to go well beyond their usual game plan to better understand the changed circumstances, develop greater flexibility to respond and bounce boldly on the opportunities that arise. In doing so, they will be deploying the trifecta of resilience, optionality and agility that South Africa demonstrated is so crucial for winning.(Corrects the first paragraph to show that South Africa is the second country to win three rugby world cups.)To contact the author of this story: Mohamed A. El-Erian at email@example.comTo contact the editor responsible for this story: Daniel Niemi at firstname.lastname@example.orgThis column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.Mohamed A. El-Erian is a Bloomberg Opinion columnist. He is the chief economic adviser at Allianz SE, the parent company of Pimco, where he served as CEO and co-CIO. He is president-elect of Queens' College, Cambridge, senior adviser at Gramercy and professor of practice at Wharton. His books include "The Only Game in Town" and "When Markets Collide."For more articles like this, please visit us at bloomberg.com/opinion©2019 Bloomberg L.P.