Injured Mets pitchers Steven Matz and Seth Lugo have been throwing on flat ground with no problems and should be on track to begin throwing off a mound soon, manager Terry Collins said on Wednesday.

Both the lefthander Matz and the righty Lugo have been on the disabled list retroactive to March 30 with what the club has termed inflammation in their respective throwing elbows. Each has reached 120 feet in their respective throwing programs.

“They have thrown so far without any discomfort which is a good sign,” Collins said.

Making progress

Infielder Wilmer Flores is out of a local hospital. He has reported to the Mets’ complex in Florida, where he will soon begin baseball activities.

Flores had been stricken with an infection, which required hospitalization over the weekend to so that antibiotics could be administered intravenously.

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Both Flores and first baseman Lucas Duda (hyperextended left elbow) are eligible to come off the disabled list on Monday. But Collins the timetable for a return is unclear for both.

Said Collins: “We’ll find out more later in the week.”

Reshuffling the deck

The Mets promoted infielder Matt Reynolds from Triple-A Las Vegas on Wednesday. Lefthander Sean Gilmartin was sent down.

The move restored a full five-man bench for the Mets, who had been carrying an extra reliever. But Collins said Tuesday’s rainout granted the bullpen a needed night of rest and lessened the need for an additional arm.

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Gilmartin will resume starting games in Las Vegas, where he will serve as rotation depth.

The Mets are carrying three catchers with Kevin Plawecki still on the roster behind the starter Travis d’Arnaud, who had been plagued with a bruised wrist. D’Arnaud started on Wednesday for the first time in a week.

Pitching matchups

Noah Syndergaard faces R.A. Dickey in Thursday’s series finale, in a matchup of the arms that highlighted what could be a pivotal trade in Mets history.

The Mets mistakenly announced that Syndergaard would pitch on Wednesday after Tuesday’s rainout.

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Matt Harvey, Jacob deGrom and Zack Wheeler will pitch against the Nationals beginning Friday.

Rehab assignment

Outfielder Brandon Nimmo began a rehab assignment with Class-A St. Lucie on Wednesday. He had been sidelined with both a hamstring and a hand injury. Nimmo led off and played centerfield.