While jubilant Rangers began their celebrations, Kim disappeared down the tunnel refusing interview requests.

Tan Chun-lok, the Kitchee midfielder, said his team was experiencing “a low moment”, and acknowledged confidence had plunged. Asked about Kitchee’s managerial situation, Tan said: “I don’t know anything”, before revealing the club had asked players not to comment.

Kitchee remained in with a quadruple chance at the beginning of May, following their Senior Shield success in February. A league defeat by Eastern, coupled with leaders Lee Man’s relentless form, have put paid to Kitchee’s chances of a fourth straight title, although their hopes are not mathematically finished.

Ken Ng Kin, the Kitchee president, who appointed Kim in place of treble-winning boss Alex Chu Chi-kwong, hinted this month that the South Korean’s future depended on achieving FA Cup and Sapling Cup success.

“If we win three trophies, it is different from winning just one,” Ng told the Post. “What we do in the short term will depend on that.”

Ng was approached for comment on Wednesday night, but the omerta around Kitchee’s head coach plans continued.

Rangers have endured a largely flat campaign, after finishing third last season to qualify for Asian football. They have lost 12 of 19 league games, and navigated a brief public fallout between Philip Lee Fai-lap, the owner, and the Japanese forward Yumemi Kanda.

It was Kanda who supplied the cross for the decisive goal when Ibrahim, all alone on the edge of the six-yard box, glanced his finish beyond Kitchee’s impressive 16-year-old goalkeeper Tuscany Shek.

“It is the club’s first trophy for a long time, so it really means a lot,” Ibrahim said.

“We came so hard into last year’s FA Cup final, and ended up really disappointed. We did our homework this time, and approached the game well. When you have confidence in yourself, you don’t need to be scared of any opponent.”

The vociferous Rangers fans among a bumper 3,769 crowd hollered for the final whistle during six added minutes.

Kitchee, however, never genuinely threatened to level. Chan Kun-sun, the Rangers goalkeeper, was not asked to make one save in the match.

The beaten finalists were predominantly reduced to wild shots from distance. A joyless display was pockmarked by poor final balls, and an alarming lack of energy and ambition. Charlie Scott, Max Poon Pui-hin and Fernando were all withdrawn early in the second half. By whom remains a mystery.

Replacements Jakob Jantscher, Juninho and Sherzod Temirov were unable to inject the required thrust, as Rangers came closest to the game’s second goal, with a free-kick whistled narrowly over by Kanda.

Kitchee were ultimately reduced to swapping defenders, introducing 36-year-old Andrew Russell and Helio Goncavles, 38, for the struggling pair of Sedin Ramic and Kuerban Yibulayimu.

Watching Kitchee send for the ageing cavalry felt ironic in a competition designed to provide youngsters with their first-team chance.

Lee, the celebrating Rangers owner, who will relinquish his club directorship at the end of the campaign, said: “Kitchee are not as strong as before, and our under-23 players are better than theirs.”

Lam Ka-wai, the winning captain, playing his last game of professional football, did not want to comment on former club Kitchee’s problems.

“It has been a perfect day,” he said.