When Oscar Washington Tabárez left the Uruguay job after the 1990 World Cup, he had regrets. He had led Uruguay to the second round, winning their first finals match in 20 years, and had begun the process of rehabilitating the nation's football reputation after the brutality of the 1986 World Cup, but he felt he could have done more. As he reflected on that in Cape Town last year, after his Uruguay team had lost to Holland in the World Cup semi-final, he seemed a man who had achieved redemption both for himself and for his country.

Many would have left it at that, protecting their reputation, satisfied with what they had achieved, but Tabárez, now 64, stayed on. He might have destroyed his legacy, but he saw more progress to be made, and he was right. If Uruguay beat Paraguay in El Monumental on Sunday night, they will win the Copa América for a 15th time, moving ahead of Argentina to take first place in the all-time rankings. Doing it on Argentinian soil, in front of a significant portion of the 600,000 Uruguayan immigrants who live in the Buenos Aires region, would make the achievement even more special.

Tabárez took over the national team for the second time after their failure to qualify for the 2006 World Cup. He immediately culled several senior players and put in place plans for 2010 and beyond, overhauling the youth structure. There were glitches on the way, and they qualified for the World Cup only after beating Costa Rica in a play-off, but patience has paid off.

"In the last five years there has been a comprehensive training process," he says. "Youngsters have to study, to learn about competitive football. Youth teams have to play against foreign opposition, to play outside Uruguay and try to adapt to world football. It's from those processes that have emerged [Nicolás] Lodeiro, [Martín] Cáceres, [Sebastián] Coates, and [Edinson] Cavani."

Tabárez has also sought to change the attitude to Uruguay's proud football history, which at times came almost to seem a burden because of the impossibility of living up to a past that included two World Cups and two Olympic golds. The aggression and cynicism of the sides of the 80s was surely in part motivated by a frustration that the triumphs of the first half of the 20th century were not being repeated.

"There's been a change of mindset in us all," he says. "This is really a quite different time to the era that was so special for us. We thought we had to win, and so we would say silly things like we could not celebrate being second. Now we're not waiting to become champions to go out celebrating, we have to assimilate each win. Furthermore, this has led a change in the way the team competes."

There is still a ruggedness and a pragmatism to Uruguay's play – with a population of just 3.5 million, there is no place for the theorising of the Argentinians or the aesthetic romanticism of the Brazilians – but it is tempered by the attacking flair of Diego Forlán and Luis Suárez, the two players who should tip the final Uruguay's way. afternoon they meet a side in their own image, the ethos of modern Paraguayan football having been shaped by Sergio Markarián when he was Olympic coach in 1992. Now 66, Markarián, a Uruguayan, coached Peru at this tournament and was coach of Tabárez in his final days at Bella Vista in the 70s.

"It's obvious that when you're picking a national team you have to pick the best players, but you must also choose a team," Forlán says. "You have to have a proper system of play." Tabárez has done that, and has also instilled great spirit. "We're close on and off the pitch," Forlán adds. "I never thought this could happen in a squad, but I'm living through it."

He, and Uruguay, are also living through an unanticipated golden period. It is not like the 1920s and early 30s when they were the best team in the world, but it's as good as it's going to get in the modern world. To a large degree that is down to the genius of Tabárez. His redemption is here.