Since 1991, Rafael Nadal was the only player who managed to capture both the under-14 World Junior Tennis and under-16 Junior Davis Cup as the winning team's No. 1 singles player. This past weekend, Jason Kubler became the second player to do so when he led Australia to a 2-1 win over England to clinch the JDC in San Luis Potosi, Mexico.

Over the years, there had been two cases where the same player competed in both WJT and JDC finals as his team's No. 1 singles player but, unlike Nadal and Kubler, they failed to lift the silverware twice in succession.

In the 1992 WJT final in Japan, Austria's Markus Hipfl defeated U.S. number one Geoff Abrams, 6-4, 6-0, to secure the trophy. In the JDC final two years later, however, Hipfl lost to Raemon Sluiter at the one spot before the Dutch won the deciding doubles to complete the turnaround victory.

In 2001, Jorge Aguilar won the JDC for Chile by beating Germany's Marcel Zimmermann, 6-0, 6-1, at number one singles after his teammate Guillermo Hormazabal had handed over a 1-0 lead.

In the 1999 WJT final, however, Jo-Wilfried Tsonga beat Hormazabal to give the French a 1-0 lead before Aguilar went down against Richard Gasquet at the one spot, 7-6, 3-6, 6-4, that sealed the Chileans' fate.

Then Nadal arrived on the scene, upped the ante, and took things to a whole new level.

In 2000, he first clinched the WJT title for Spain when he beat Russian No. 1 Nikolai Soloviev, 6-3, 6-2, in the final to establish an unassailable 2-0 lead for the Spaniards. Two years later, he defeated USA's Brendan Evans at the one spot, 6-2, 6-2, to seal the Junior Davis Cup for his side.

Since Y2K+1, no same player had featured in both finals, let alone finishing on the winning sides for either events. However, that changed in San Luis Potosi last Saturday.

Jason Kubler (ITF 89), second behind Bernard Tomic in the Australian pecking order, beat England's George Morgan at the one spot to level the final against England at one apiece. Then he collaborated with Joey Swaysland, who happened to have played No. 2 singles two years ago, to win the decisive doubles, 6-1, 7-5, to cement the JDC for the Aussies.

Two years ago in Prostejov, Kubler led his country's under-14 team to WJT glory when he beat Czech number one, Lukas Vrnak, 6-4, 6-3, to wrap up the final after Swaysland had given the Aussies an early advantage by disposing of Robert Rumler in three sets.

Similar to Rafa's all-conquering display seven years ago, Kubler also won all his match-ups at the one spot in Mexico last week without dropping a set.

Holistically speaking, while such a crude comparison of stats can only suggest that for one reason or another, being the numero uno in one age group is not an antecedent to scaling the same heights in the next age group, perhaps it does imply that it takes a special kind of player to duplicate the WJT-JDC double.

In all likelihood, nonetheless, the name Jason Kubler should appear again in the not-so-distant future.

Although Australia has come under fire in recent years for having just one player ranked in the ATP Top-100 – Lleyton Hewitt – Kubler, together with Tomic, not to mention the addition of Todd Woodbridge in the mix, there is ample reason to suggest things are looking up once again.

The World Junior Tennis competition, the International Team Competition for players aged 14 & under, was started by the ITF in 1991. The International Team Competition for players aged 16 & Under was launched by the ITF in 1985 as the "World Youth Cup" with NEC as the title sponsor between 1988 and 2001, and then re-branded as part of a new partnership with BNP Paribas to "Junior Davis Cup by BNP Paribas" in 2002.

World Junior Tennis – Boys' Winners

Junior Davis Cup by BNP Paribas – Winners