The Mets face Brandon Cumpton, Edinson Volquez and Charlie Morton at Citi Field.METS (22-27, fourth place/NL East) vs. PITTSBURGH PIRATES (22-27, fourth place/NL Central)

Monday: RHP Jacob deGrom (0-2, 2.77) vs. RHP Brandon Cumpton (0-1, 4.26), 1:10 p.m. ET

Tuesday: LHP Jonathon Niese (3-3, 2.70) vs. RHP Edinson Volquez (2-4, 4.37), 7:10 p.m. ET

Wednesday: RHP Bartolo Colon (3-5, 5.34) vs. RHP Charlie Morton (1-6, 3.29), 1:10 p.m. ET

Pirates short hops

• Right-hander Brandon Cumpton was selected to replace Wandy Rodriguez in the rotation and will start the series opener against the Mets. Cumpton, 25, received the nod over Jeff Locke.

Rodriguez was designated for assignment after surrendering six runs and failing to complete the second inning against the Baltimore Orioles on Wednesday. He had an 0-2 record and 6.75 ERA in six starts. Rodriguez is making $13 million this season, although $5.5 million of that amount is the responsibility of the Houston Astros.

Cumpton was 4-1 with a 1.35 ERA in six starts with Triple-A Indianapolis. He made two starts for the Pirates earlier this season.

• Ike Davis is hitting .347 (25-for72) in 22 games in May. He has reached base in 20 of 22 games this month. Davis was acquired from the Mets on April 18 for reliever Zack Thornton and a player to be named. That other player is expected to be announced next month because he came from the 2013 draft.

Davis replaced third baseman Pedro Alvarez in the cleanup spot on Friday. Alvarez, dropped to No. 6 in the lineup, is hitting .209 with nine homers and 28 RBIs.

• 2013 National League MVP Andrew McCutchen is hitting .325 (26-for-80) in 21 games this month. McCutchen comfortably beat runner-up Paul Goldschmidt from the Arizona Diamondbacks for last year’s award.

• Neil Walker leads NL second basemen with 10 homers and 26 RBIs. Walker’s 10th homer last season did not come until Sept. 2.

• Edinson Volquez signed a one-year, $5 million contract with the Pirates on Dec. 11. He began last season with the San Diego Padres and, after his Aug. 27 release, latched on with the Los Angeles Dodgers. Volquez surrendered four homers at Yankee Stadium two starts ago, but rebounded to limit the Washington Nationals to one run six innings on Thursday.

• Riding the hot hand, the Pirates have started Josh Harrison in right field for the past six games.

• Reliever Mark Melancon has not allowed a homer in 86 innings, the longest active streak in the majors. He last surrendered a long ball on April 14, 2013, against Cincinnati’s Joey Votto. Melancon has nine saves in 11 chances this season.

• Closer Jason Grilli returned from the disabled list on Friday. He had been sidelined since April 21 with a left-oblique strain.

• Charlie Morton snapped a six-game losing streak over his first nine starts this season by limiting the Nationals to one run in 5 2/3 innings in an eventual 4-3 win Friday.

• Catcher Russell Martin returned from the disabled list Thursday. He had been sidelined since April 26 with a left-hamstring strain.