They designated right-handed pitcher Buddy Carlyle for assignment in a corresponding roster move and the team has 10 days to trade him, ask for release waivers or outright him to the minors.
Niese has been on the disabled list since July 6 and is scheduled to start Monday's game against the Seattle Mariners. Niese was shelved in spring training with shoulder weakness and missed six weeks last season with a partial rotator cuff tear.
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Niese is 5-4 with a 2.96 ERA, 1.21 WHIP, in 103.1 innings this season for the Mets, who are eight games back of the Washington Nationals in the National League East.
- Scooby Axson