Super Bowl LI was supposed to be a shining moment for Tiffany & Co., which bought its first-ever ad for the big game.

Instead, the venerable jeweler — who designed the famous trophy hoisted by the Patriots Sunday night in Houston — booted its chief executive, Frederic Cumenal, effective immediately, just two hours before kickoff and four hours before its new pitchwoman, Lady Gaga, took the stage as the half-time act.

None of Tiffany’s top brass were at the game, the company said.

“The timing seemed odd,” said Brian Yarbrough, an Edward D. Jones & Co. analyst, echoing what many close to the company and industry observers said seemed like an abrupt turn of events for a company that had been making steady progress in turning around its sagging sales.

“Tiffany’s results had been sequentially improving,” said Instinet analyst Simeon Siegel.

Others believe the shake-up was the culmination of simmering tensions between Cumenal and Chairman Michael Kowalski — Tiffany’s former longtime CEO — who exchanged heated words a few months ago over Tiffany’s former design director, Francesca Amfitheatrof, according to sources.

Amfitheatrof, who was responsible for revamping Tiffany’s jewelry designs, was recruited by Cumenal in 2013. They were said to have a warm relationship, but on Jan. 17, Tiffany announced her departure “to pursue other opportunities,” elevating Reed Krakoff, a former superstar at Coach, who had been tapped in July as a consultant to relaunch an accessories collection. Krakoff was promoted to a new position, chief artistic officer.

“The suddeness of Cumenal’s departure was surprising,” said one source close to the company. “Everyone was like ‘what’s going on?’ ” Others describe it as a power struggle between Cumenal and Kowalski, who’d lead the tony firm for 16 years, stepping aside in 2015. Cumenal has been in leadership positions with the company since 2011.

“Mike was pretty blunt in his comments (about Cumenal leaving) and you usually don’t see that when a CEO leaves,” Yarbrough said.

Kowalski, who will serve as interim CEO while the company conducts an executive search, said the board “has been disappointed by recent financial results.”

A spokesman for the company did not respond to a query from The Post about friction between the executives over the Amfitheatrof’s departure.

“They had an out and out fight and Frederic was upset,” said a source familiar with the relationship. “There was a sense that things weren’t working out and they had a disagreement over her.”

Tiffany’s stock fell 2.5 percent, to $78.49, Monday after its CEO shake-up.

Sales at US stores open for at least one year fell 4 percent compared to a year ago during the critical holiday shopping season, while sales at its Fifth Avenue flagship fell 14 percent, the company said, blaming the heavy security surrounding its neighbor, Trump Tower.

Our editors found this article on this site using Google and regenerated it for our readers.