A historically disappointing and expensive season has led to a historic sell-off.

The Mets have traded six Cy Young Awards at one deadline.

After shipping out Max Scherzer on Friday, the Mets have a deal in place to send Justin Verlander back to the Astros on Tuesday, The Post’s Jon Heyman confirmed.

It marks the end of the brief co-ace era and further stamping this season — which featured the biggest expenditure in MLB history — as a failure.

Verlander has a no-trade clause that he will waive, Heyman reported.

It is unclear what prospects the Mets are getting back in return.

Steve Cohen and Billy Eppler’s club will punt on the final two months of this season and have begun building for the future.

If Verlander’s $33.5 million option in 2025 vests, he would be owed about $93 million through the end of his contract.

The Mets already had traded Scherzer (to the Rangers), David Robertson (Marlins) and Mark Canha (Brewers). The most obvious trade chip remaining is Tommy Pham.  

The Mets, with a middling farm system, have used Cohen’s wealth and willingness to absorb outgoing contracts to extract prospects from other clubs.

In dealing Scherzer, the Mets landed infielder Luisangel Acuna, who is now their No. 2 prospect, according to MLB Pipeline.

The Robertson deal landed Marco Vargas (No. 7) and catcher Ronald Herandez (No. 19), and shipping out Canha netted righty Justin Jarvis (No. 13).

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Verlander, meanwhile, has been traded to Houston at a trade deadline for a second time.

He went from the Tigers to the Astros in 2017, when he helped the club win a World Series, and was a superstar with the Astros until signing with the Mets this offseason.

Verlander opened the season on the IL with a muscle strain, debuted in early May and was merely OK through most of June, as the Mets nosedived.

Verlander has looked more like the three-time Cy Young winner he is in his past seven starts, in which he has posted a 1.49 ERA that has brought his season mark down to 3.15. 

It was too late to save his club but timely enough to save his trade value.