“I think I was more right in introducing syrah than people who introduced cabernet sauvignon,” he said. “My biggest responsibility is not to bobal, it’s to Manchuela.”

Still, bobal is the most distinctive variety the region has to offer, and in the right hands, as at Bodegas Ponce, the wines can be fascinating. The tannins are firm, yes, but the grape also has great acidity and freshness and can transmit the nuances of terroir.

“Serious bobal has been made only over the last 20 years,” Mr. de la Serna said. “Does it age? It’s not yet clear.”

A ‘Mystical’ Grape

If anybody can make the case for bobal, it would be Mr. Ponce (pronounced PAHN-thay), whose wines are the most nuanced and energetic of the Manchuela producers I have tasted. Mr. Ponce, whose family is from the nearby town of Iniesta, worked with Telmo Rodríguez, a leading producer who makes wines all over Spain, before returning to Manchuela to concentrate on his own wines. In 2017, he moved into his own new winery.

Mr. Ponce manages a network of old vineyards, which he farms biodynamically, each of which shows a different perspective on bobal. La Casilla, from limestone, is supremely mineral yet light and elegant. La Estrecha, which comes from granite soils, is more savory and powerful, while Pino, named for a lone pine tree in the middle of a limestone vineyard about 2,500 feet in elevation, is the most complex.

Perhaps his favorite vineyard is the 90-year-old P.F., for pie franco, meaning that the vines are ungrafted, a rarity in most of the fine-wine world. Since the 19th century, when a plague of phylloxera ravaged most of Europe’s grapevines, the solution was to graft the European vines onto American roots, which are immune to the aphid. This vineyard, though, is on sandy soils, in which phylloxera cannot survive. The wine is stony, floral, herbal and fine.