Relegated Osaka were arguably the better team throughout, but surrendered the match's lone goal on a first-half set piece to allow the Sun Kings to capture the lead
In a dramatic conclusion to relegation-stricken Gamba's season, the Kansai club pressured early and often throughout the first half with national team star Yasuhito Endo's free kicks a constant threat. Brazilian Leandro, whose mid-season arrival heralded 14 goals in 15 appearances, forced Reysol goalkeeper Takanori Sugeno to make no small number of desperate saves.
But it was a Reysol free kick in the 35th minute that resulted in the only goal of the match. Leandro Domingues' corner kick was met sharply by an unmarked Hirofumi Watanabe, whose header rocketed into the back of the net. Gamba defender Daiki Niwa was the villain on the play as he appeared to make no effort to cover Watanabe in the air.
Reysol found their attacking momentum in the second half, with several break-aways nearly leading to a second goal. But although Gamba recovered defensively, they were unable to find an equalizer against a Reysol who were content to defend until the final whistle.
The 2011 J-League champions booked a return to Asian Champions League play with the Cup win, their first since the Hitachi SC era. Reysol also became the fifth J-League club to have won all four domestic trophies: the J-League, the J-League Cup, the Emperor's Cup, and the Super Cup.
Meanwhile, Gamba are facing their first-ever stay in the J-League's second division following their 17th-place finish in 2012. The club quickly announced the long-expected replacement of coach Masanobu Matsunami with former Shimizu S-Pulse manager Kenta Hasegawa following Tuesday's result, and the lack of Asian play could hasten the departure of top players such as Endo, national team defender Yasuyuki Konno, and former Mallorca bench-warmer Akihiro Ienaga.
With club president Kikuo Kanamori also departing, the 2008 Asian champions will be faced with the task of rebuilding their front office in addition to their roster.
Reysol, who join league winners Sanfrecce Hiroshima as well as Vegalta Sendai and Urawa Reds in representing Japan, will open their second ACL campaign at Guizhou Renhe on February 27. They are also grouped with the A-League's Central Coast Mariners and Korea's Suwon Bluewings.