The home team had gone down to a wonder strike from nowhere by Hwang Ui Jo in the 15th minute before Usami - in the 64th minute - and Lins, in the 82nd, took Gamba to the top of the group.
In the end it was a well-deserved, though hard-fought win for the home team. Plenty of early possession was seen, but good pressure - high up the field - by Seongnam meant that Gamba were not able to get their patented passing game going as well as they might have wanted to.
After the goal the away team parked the proverbial bus but Gamba were patient and, as Seongnam tired and lessened the pressure the passing game developed more, space was found and, eventually the equaliser came, although a little good fortune was included in the package.
Keisuke Iwashita had come on for Shohei Oguro - filling in at right back - in the 55th minute with Daiki Niwa moving to the right, Iwashita slotting in at centre back alongside Jungya Kim. Takahiro Futagawa - making a rare start - then made way for Lins in the 58th minute as Gamba boss Kenta Hasegawa shuffled his pack looking for goals and it was Usami who gave the manager what he wanted.
J1's top scorer found himself in space on the left wing. He moved the ball to his right foot and swung in a cross that Patric just failed to connect with at close range, but the big Brazilian did enough to worry the keeper and Usami's cross/shot crept in at the far post!
Next to come on was Shu Kurata, on for Hiroki Fujiharu in the 75th minute as Hasegawa threw caution to the wind, knowing another goal was needed. Kurata managed two shots in his first two minutes on the field, but the keeper was not troubled, yet! But the changes, the perseverance of Gamba, and the tired legs of Seongnam all contributed to the pattern of the game and with eight minutes on the clock Lins got the winner!
And so, next up, Gamba take on FC Seoul as the knockout stages begin. The away leg is on May 20th, with the second leg at home at Banpaku on May 27th. Do not miss it!
Team - Higashiguchi, Ogura (Iwashita, 55), Niwa, Kim, Fujiharu (Kurata, 75), Konno, Endo, Futagawa (Lins, 58), Abe, Patric, Usami