Amid President Donald Trump's tough-sounding talk about renegotiating the North American Free Trade Agreement, economists and other observers have debated how potential changes could impact the U.S. economy.

Less scrutinized is how Mexico, the United States' third-largest trading partner and a frequent target of Trump's broadsides on trade and immigration, might be affected by adjustments to the decades-old trade agreement.

At least a few economists are outlining scenarios in which Mexico could emerge as an unlikely winner in the brewing debate. The discussion takes place against a backdrop of Mexican growth that's less than stellar, but has beaten some of the more dire predictions about how the country could fare as the Trump era takes shape.

"The Mexican economy has its problems, but it has arguably been the best-performing Latin American economy in recent years," Mark Zandi, chief economist at Moody's Analytics, told CNBC in an interview.

"It has become less dependent on the ups and downs in oil prices, and more integrated into the global supply chain," Zandi added. "Given its young population, Mexico has a bright economic future, particularly if it is able to address its problem with crime and corruption."

Indeed, citing "a more constructive mood"— one that presumably assumes NAFTA will be reformed rather than shredded — Citigroup recently upgraded its outlook for Mexico's economy to an expansion of 1.7 percent this year from an earlier projection of 1.2 percent growth. That revision was in part "predicated ... on a more constructive assessment of what the future of North American integration might look like," the bank's analysts wrote in a research note last week.

"On the relationship with the U.S. there appears to have been a rethinking of trade issues within the Trump administration," Citi said. "We now think that NAFTA will be 'rebalanced' but also 'upgraded'" in ways that may prove beneficial to Mexico, the bank added.

Citi's remarks reflected a growing consensus among analysts that Trump's hard-line approach to trade as a candidate is giving way to more practicality as a president. That dynamic was underscored when Trump told CBS in an interview last week that he was open to renegotiating NAFTA — but warned that he was willing to abrogate the pact if talks between Canada and Mexico proved fruitless.

Bigger problems than NAFTA?

To be certain, it's not all good news for Mexico. Soaring inflation and a stagnant industrial sector were a drag on first-quarter growth, two factors that loom large as the country begins delicate trade talks with the U.S. In April, annual inflation spiked to an eight-year high of 5.62 percent, a "reminder that Mexico faces other challenges besides its relationship with the U.S., and maybe bigger ones," William Adams, senior international economist at PNC Financial Services Group, told CNBC.

"If financial markets get tired of thinking about trade policy as it relates to the peso," Adams said, citing the Mexican currency's recovery from a double-digit depreciation in 2016, "They may discover that the economic fundamentals underlying the currency have weakened in the last 12 months as U.S. fundamentals strengthened."

A spark for energy reform

Mexico is a major energy producer, as well as voracious consumer of natural gas. In recent years, the United States' neighbor to the south has become a prime destination for its vast supply of natural gas exports, a part of Mexico's efforts to reform its own oil and gas sector.

"Regionally, North America is almost energy independent, reducing dependency on hostile powers. Importantly, two elements of NAFTA's renegotiation could boost both energy supply and demand in North America," Bank of America-Merrill Lynch recently noted.

"On the one hand, increased Mexican content in tax-free exports to the U.S. would lead to more Mexican industrial activity and more U.S. natural gas demand in Mexico," the bank wrote recently. Mexico's natural gas imports have nearly tripled since 2010, according to Energy Information Administration data, and that amount continues to grow.

"On the other, Mexico's energy reform presents a substantial opportunity for U.S. energy, technology, and infrastructure companies. So NAFTA stays and the world's largest energy compact emerges from it, in our view," BofA added.

At stake is a bilateral trade relationship that was worth around $525 billion in 2016, according to data from the U.S. Trade Representative's office, with the U.S. absorbing around $294 billion in Mexican imports.

Conversely, the country took in $231 billion in U.S. goods last year, a deficit that forms the crux of Trump's gripes against NAFTA and its effect on U.S. jobs. The nonpartisan Wilson Center estimated in research last year that trade with Mexico creates nearly 5 million jobs — roughly equal to the number of blue-collar positions the manufacturing sector has shed since 2000.

"Even if NAFTA should be changed in favor of the U.S., it is very unlikely that this will mean that the jobs the U.S. lost to Mexico in the decade after NAFTA was passed will ever come back to the U.S.," Zandi said to CNBC. "Those apparel, textile and light manufacturing jobs will simply go to other lower-cost producers in other parts of the world," Zandi said.