The team sent Duda back to New York earlier Saturday for an MRI of his left side after the first baseman/left fielder complained of discomfort after Friday's win.
"... He was pretty sore last night when the game was over," manager Terry Collins said Saturday afternoon. "He was still sore again today -- real sore this morning. So he's going to be unavailable today. ... He came in last night and said his side was hurting him pretty bad."
To replace Duda, the Mets called up corner infielder Zach Lutz from Triple-A Las Vegas.
Daniel Murphy started at first base and went 2-for-5 with an RBI in Saturday's 8-7 loss to the Philadelphia Phillies. Murphy had started six consecutive games at that position earlier this month while the Mets auditioned Jordany Valdespin at second base, which Murphy typically mans.
Ike Davis could've been a candidate to return from Triple-A Las Vegas, Collins said earlier Saturday, but a team source said Saturday night that Davis needed more time in the minors.
Davis was demoted June 9 with a .161 average and 66 strikeouts in 186 at-bats. He has produced consecutive two-homer games with the Pacific Coast League club and is hitting .333 with a .480 on-base percentage in 11 Triple-A games.
General manager Sandy Alderson had been in Tucson, Ariz., this week watching Davis and the PCL team.
Duda began the season as the left fielder before shifting to first base, his natural position, on Monday.