Alderson said the right-hander had been sent home, but declined further comment.
Plawecki told reporters Saturday that he had nothing to do with the incident.
Harvey can appeal the suspension.
At 28 years old, Harvey still has time to revamp. Harvey apologized and was fined but offered no explanation. He says he advised the team of the situation.
I don't think the Mets should be one of them.
When I threw out the idea of trading Harvey on Twitter, value became the word shouted back at me.
Coming off two straight playoff appearances, the Mets began this season with lofty expectations.
They lost not one, but two third baseman to injuries. It is hard enough to deal with that; now the Mets are dealing with another issue involving starting pitcher Matt Harvey.
The Miami Marlins came about as close as possible to producing a combined no-hitter Sunday afternoon.
Russian Federation presents greatest threat to USA , says Federal Bureau of Investigation chief
And he even quizzed Comey as to whether he had been the source of leaks to the media about investigations into Trump or Clinton. Asked about WikiLeaks, Comey said he thought the anti-secrecy group was engaged in something more sinister than journalism.
Collins told the media in the Mets clubhouse that the information about Harvey would be kept in-house where it should be.
We'll see how the Mets plan on going forward because right now they could use all the help they can get.
The suspension removed Harvey from the 25-man roster. The very next Sunday, Harvey is suspended and the Mets get one-hit by the Marlins, and Giancarlo Stanton gets to have batting practice against a journeyman Minor Leaguer, Adam Wilk, who had to be flown in from Albuquerque to take Harvey's place. He's a big figure in NY and that's a big city to be a big figure in.
Harvey, who is coming back from thoracic outlet syndrome surgery performed past year that ended his season last July, is now 2-2 with a 5.14 ERA in six starts.
A break may be just what Harvey needs to get out of his own head and back to pitching like the World Series Ace he was before his season was cut short. "Anybody in that room that misses a day and nobody knows about it, we've got to do the same thing".
The New York Mets have scratched Harvey for his scheduled start Sunday, May 7, 2017, against the Miami Marlins and suspended the right-hander three days for a violation of team rules.
In his return this season, the 28-year-old has continued to throw harder, yet his once-high strikeout rate has dropped to 5.14 per nine innings which is well-below average among Major League Baseball rankings.
It's just the latest issue in a long line of questionable moves involving the pitcher that has frayed his relationship with the team.