Carlos Correa‘s physical is giving the Mets pause:

The New York Mets and free agent shortstop Carlos Correa are “working through” a medical issue after his physical with the team apparently showed the same right leg concerns which nixed a deal with the San Francisco Giants earlier in the week, according to a source familiar with the situation.

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Despite the latest delay, a deal with the Mets is still likely, according to the source, but the contract could be reworked to account for the issue. That reworking could simply be for fewer years and less money or could include language which doesn’t guarantee a certain amount of money if Correa misses lengthy time due to the specific leg ailment.

ESPN.com

So it seems like the issue the Giants saw is real enough so that the Mets might alter the offer. The Giants, who seem more risk adverse, never seem to have gotten to the point of reopening the negotiation. According to the article, the concern is related to a broken fibula Correa suffered in 2014.