The Houston Astros' illegal sign-stealing methods were brought to the Washington Nationals' attention prior to the 2019 World Series, thanks to Alex Cora.

The former Boston Red Sox manager reached out to Nationals skipper Dave Martinez to warn him about Houston's sign-stealing, according to Barry Svrluga and Dave Sheinin of the Washington Post. Cora was involved in the Astros' sign-stealing operation while serving as the team's bench coach in 2017.

Svrluga and Sheinin also note several Los Angeles Dodgers players warned Nationals infielder Brian Dozier -- who played with L.A. in 2018 -- about Houston's sign-stealing.

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On top of that, Nationals ace Max Scherzer asked former Astros reliever Tony Sipp if Washington should be concerned about the Astros, even with no runners on base. Sipp said yes.

In other words, the Astros' sign-stealing wasn't much of well-kept secret in MLB before the bombshell report from The Athletic dropped in December.

The fallout from the report has resulted in the firings of Astros manager A.J. Hinch and general manager Jeff Luhnow. Former Astros player Carlos Beltran stepped down from his new position as New York Mets manager, and Cora mutually agreed to part ways with the Red Sox.

On Tuesday, it was announced Ron Roenicke will replace Cora as Boston's interim manager.