PILAR, Argentina - They run on turf, they run on dirt, in the slop, on firm, good, and soft ground. If races were run over broken glass, they would run on that too, and win more than their share of them. They are Argentine-breds, and their accomplishments around the world are testimony to their gaucho-like toughness. We know them most recently from the exploits of Bayakoa, Paseana, and Gentlemen, but their fame spreads far and wide, throughout South America to South Africa, and stretches back to the 1870's with the founding of the Argentine Jockey Club by Carlos Pellegrini. Leave the bustling streets of Buenos Aires and a one-hour ride will plant you in horse country. Famous for its beautiful estancias, or ranches, Argentina is not only one of the world's leading Thoroughbred breeding countries, it is also the breeding grounds for the world's best polo ponies and polo players. It is in this setting that one finds Haras La Quebrada, Argentina's leading Thoroughbred breeder 13 times in the last 21 years. Located about 45 miles northwest of Buenos Aires near Pilar, La Quebrada is typical of the many family-run Argentine breeder/owner operations - including Haras Vacacion (the breeder of both Paseana and Bayakoa), Haras Firmamento, and Haras La Biznaga - which recall the golden age of American racing when the Wideners, the Whitneys, the Vanderbilts, the Wrights, and the Taylors dominated American racing. In spite of its current economic woes, Argentina is going through a sort of Golden Age of its own right now, and Haras La Quebrada is the shiniest nugget of all. Founded in 1945 by the late Hernan Ciriani, it was the first Argentine stud farm to import an American stallion (Salt Marsh). More recently, La Quebrada hit the jackpot when Ciriani's son, Hernan II, imported Southern Halo. A 19-year-old son of Halo, he has made a splash of international proportions. He has been the leading stallion in Argentina every year since 1994. Through 2001 he has sired 98 worldwide stakes winners who have won 223 black-type races. Among his offspring are six-time Group 1 winner El Compinche, champion sprinter and three-time Carrera de las Estrellas winner Wally, and Team, the Argentine horse of the year as a 2-year-old in the 1997-98 season. All were trained by the master of La Quebrada, Juan Carlos Etchechoury. Horses more familiar to Americans sired by Southern Halo are Spinster Stakes winner Miss Linda and Serenita, twice placed in Grade 1 races in the U.S. Southern Halo is about to return to La Quebrada from Gainesway Farm for the Southern Hemisphere breeding season that begins this month. He will join his sons El Compinche and Handsome Halo, as well as fellow Northern Hemisphere travelers Victory Speech, Luhuk, and Mutakddim. However, Louis Quatorze, who spent the last three Southern Hemisphere breeding seasons at La Quebrada, will not return this year as the economic crisis makes it impossible for Argentine breeders to mate with him because of the drastic devaluation of the Argentine peso. Americans often wonder how Argentine-bred horses manage to do so well in the United States. Hernan Ciriani III, the 29-year-old son of La Quebrada's current headman and heir to the throne, offers an insight while explaining just why Argentine steaks are the best in the world. "Farmers give the cows plenty of room to roam," he explained. "This makes for a happy animal who produces a higher grade of beef. Of course the grass might have something to do with it too." Ciriani noted that the same practices apply to Thoroughbreds. The paddocks at La Quebrada are gigantic. The farm at Pilar and a second farm in Santa Fe province both measure in the 1,000-acre range, large enough for paddocks that could hold five or six football fields. Happy horses run better than unhappy horses, and the Argentine Thoroughbred, who has the further advantage of mild winters, is a happy animal. Even the stalls at La Quebrada's training center at San Isidro, built by the British in the early 20th century, are a roomy 20 feet by 20 feet. La Quebrada horses also get the best of care. The Cirianis - father and son - employ 30 veterinarians to tend to their needs. They are led by Dr. Horacio Houssay, the great-nephew of Bernardo Houssay, a Nobel Prize winner for physiology, and a consummate horseman who pointed out another reason why Argentine horses do so well on both dirt and turf. "The grass on the turf track at San Isidro" - where all of Argentina's turf racing is held - "is much shorter than in Europe or America," he said. "That makes it easier for horses here to switch back and forth between the two surfaces." With 13 championships in 21 years, Haras La Quebrada is not a farm to sit on its laurels. The tireless Hernan II, the driving force behind the highly successful Carrera de las Estrellas, which had its 12th running last Saturday, is in charge of an operation that disdains celebrations of big race wins in favor of the work ethic. "My father runs a working farm," Hernan III points out. "Sometimes people ask why we are not celebrating late at night, so I must explain to them that we have to get up early in the morning to go to work." The future of Haras La Quebrada is now. Among the newly turned 2-year-olds they bred who will soon be making their debuts are Mr. Nancho, a full brother to Miss Linda; Select Me, a full brother to Serenita; Go On, a Louis Quatorze half-brother to Polla de Potrillos winner Golfer; South Victory, a Victory Speech colt out of six-time group race winner Southern Filly; and Victory Again, a Victory Speech half brother to three group race winners. Among their top juvenile fillies are Fortisima, a Southern Halo half to three-time Group 1 winner Fontemar; Welcome, a full sister to their great champion Wally; and Wendys, by Victory Speech out of the great Wally herself. Since 1980 Haras La Quebrada has won 43 Pellegrini Awards, Argentina's equivalent of the Eclipse Award. With a roster of juveniles like it has this season and a team of devoted professionals to guide them, future championships seem assured.