Marcin Tybura has an undisclosed illness. David Yeazell-USA TODAY Sports

These days, Ultimate Fighting Championship fights are not official until the cage door locks behind the competitors.

Shortly after the UFC 273 weigh-ins concluded, the promotion announced that the heavyweight contest between Marcin Tybura and Jairzinho Rozenstruik had been canceled. Tybura suffered an undisclosed illness, and the promotion did not state if it was related to COVID-19 like it has for other recent illness scratches. Tybura (253) and Rozenstruik (252.5) both made weight without issue.

This is the second time this matchup has been nixed, with the two first booked against one another for UFC Fight Night 202 in February. For undetermined reasons, the fight was pushed back to the April 9 event. There will be no replacement for Tybura as the weigh-ins have already been completed, and the UFC did not state if the fight will be rebooked at later date or if the two will go their separate ways.

Tybura was aiming to rebound from his first defeat since 2019, as he fell short to Alexander Volkov at UFC 267 in October 2021 by decision. That setback snapped a five-fight win streak over the likes of Sergey Spivak, Walt Harris and Ben Rothwell. Before his victorious stretch that began in 2020, the Polish fighter actually sustained a UFC record below .500, with four victories opposite five losses.

Suriname’s Rozenstruik too was looking to bounce back from a loss, with a decision defeat to Curtis Blaydes in September 2021. The former kickboxer has alternated wins and losses in his last six, with all of his triumphs coming by knockout. His three career losses have come against top names in the division, succumbing to a quick knockout from current champion Francis Ngannou first, followed by subsequent decision losses to ex-interim champ Ciryl Gane and top contender Blaydes. Wins over Alistair Overeem, Junior dos Santos and Andrei Arlovski earned him a spot among the top 10 at heavyweight.

Rozenstruik wished his former opponent well in a briefstatement shortly after the news broke.

"What's up guys, some bad news here," Rozenstruik said with a sigh. "The fight with Marcin Tybura got canceled, Marcin is sick and there's nothing we can do...and just [I] wish him a speedy recovery and hopefully we see him next time around. For now, I talked with the UFC, discussing what the available options are, and you guys will hear soon."

UFC 273 is down to 12 fights at the Vystar Veterans Memorial Arena in Jacksonville, Fla., on April 9. The main event will be a featherweight title clash when Alexander Volkanovski meets Chan Sung Jung, while the co-headliner features a bantamweight championship unification battle and rematch between Aljamain Sterling and Petr Yan. Before those two bouts for belts, Gilbert Burns and Khamzat Chimaev will throw down in a highly anticipated welterweight collision.

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