It was Major League Baseball's worst nightmare come true at the World Baseball Classic. 

A star player on a World Series contending team, fresh off signing a nine-figure contract, suffers a potential season-ending injury roughly two weeks before Opening Day.

That means the New York Mets will be without their All-Star closer Edwin Diaz, who reportedly is expected to miss the entire 2023 season after reportedly suffering a torn patellar tendon in his right knee on Wednesday. 

Despite the bizarre nature of the injury, which occurred during a celebration after Puerto Rico's victory over the Dominican Republic, it has led some to question the timing and necessity of the World Baseball Classic. 

It has also raised concerns about whether highly-compensated players who are vital to the success of the teams that pay their salaries should be risking injury when, technically, not on company time.

The loss of the player, of course, is the greater cost than the salary itself. 

Most injuries sustained during the World Baseball Classic are covered by insurance, which will likely protect the Mets financially for the $19.65 million Diaz is owed this upcoming season.

Here's how the insurance process works for players competing in the World Baseball Classic...

What happens when a player gets injured during the World Baseball Classic?

There's a reason Los Angeles Dodgers star pitcher Clayton Kershaw isn't playing in the World Baseball Classic despite expressing his desire to do so. 

His insurance was denied.

According to Jorge Castillo of the Los Angeles Times, a premium is negotiated with an insurance company that covers WBC players who are on 40-man MLB rosters. Players competing in the tournament must undergo physicals, and their medical records are reviewed by an underwriter. Each player is then deemed either "insurable" under that premium or "uninsurable."

A player injured during the World Baseball Classic receives their full guaranteed MLB salary, which their team is reimbursed for by the insurance company for the time missed. 

A player is determined to be "uninsurable" for a variety of reasons, Castillo reports, including having a “chronic condition” based on injury history or having spent considerable time on the injured list the season prior to the WBC.

The 34-year-old Kershaw, who has been prone to injury during a Hall of Fame career, was deemed "uninsurable." That meant if Kershaw participated in the World Baseball Classic and suffered an injury, the Dodgers would be liable for the time he missed under his one-year, $20 million contract signed in December.  

The Dodgers did not waive Kershaw's insurance requirement - as the Detroit Tigers did for the 39-year-old Miguel Cabrera and his $32 million salary, per Castillo. That led to Kershaw attempting to pursue, and failing to secure, his own insurance claim that would have covered his MLB salary if he was to sustain an injury during the WBC. 

Will Edwin Diaz be paid for the 2023 season?

Yes, even if Diaz misses the entire season, his MLB contract is guaranteed. 

Assuming the 28-year-old pitcher was deemed "insurable" by the underwriter, his salary will be covered by insurance and the Mets will be reimbursed for the time Diaz misses. 

But the team would much rather have their closer available for a potential World Series run.