In an offensive slump, New York called up the first baseman from Triple-A Buffalo. And Davis didn't disappoint, going 2-for-4 and following slumping Jason Bay's RBI double in the seventh with a run-scoring hit.
New York's Jonathon Niese allowed a run against the Cubs, who haven't been hitting either. Like the Mets, Chicago entered having scored five runs in the past two games.
The Cubs, who lost two in a row to Houston over the weekend, shuffled their lineup against the left-handed Niese, moving Marlon Byrd into the leadoff spot and dropping Ryan Theriot to eighth. Xavier Nady and Aramis Ramirez flopped spots with Nady batting fourth, and Geovany Soto moved up to seventh.
Niese went 5 2/3 innings and allowed eight hits and an unearned run, striking out seven. Fernando Nieve (1-0) pitched 1 1/3 innings for the win after.
Chicago's Randy Wells — who singled twice — only allowed a run himself, but the Mets rallied against the Cubs' bullpen.
Jose Reyes, who did not start and was in an 0-for-17 slump and hitting .154 since returning to lineup on April 10 after sitting several weeks because of a hyperactive thyroid, was hit by a pitch from James Russell (0-1) to start the seventh.
Gary Matthews Jr. struck out after failing to sacrifice Reyes over before Pagan homered several rows into the seats in left-center for the Mets' first extra-base hit since Matthews doubled in the ninth inning Friday night at St. Louis.
The drought included New York's 20-inning win Saturday.
Bay added an RBI double and after Jeff Francoeur reached on an error by third baseman Ramirez, Davis made it 5-1 Mets. Francoeur scored on Sean Marshall's wild pitch to make it 6-1.
Davis will take over at first base for Mike Jacobs, who was designated for assignment on Sunday, while Daniel Murphy recovers from a sprained knee.
Byrd appeared comfortable in the top spot. He had three hits, driving in a run in the sixth that tied it at 1. He was hit in the helmet with a pitch in the ninth by Jenrry Mejia but quickly picked up his helmet and ran to first.
After Niese worked out of a bases-loaded jam in the fifth, Luis Castillo chopped an RBI single over Wells' head for a 1-0 lead in the bottom half.
The Cubs scored an unearned run in the sixth. Niese walked Soto and Wells got his second hit with two outs in the inning to end Niese's night. Soto went to third on Wells' infield hit when Davis couldn't scoop Alex Cora's throw from shortstop out of the dirt.
Byrd then greeted reliever Nieve with a run-scoring infield single to tie it.
Notes
Cubs left-hander Ted Lilly was scheduled to make his second minor league rehab start. He could return to the Cubs rotation this weekend against Milwaukee. … The Mets celebrated Jackie Robinson Day because they were on the road April 15, the anniversary of the Brooklyn Hall of Famer's breaking baseball's color barrier. Both teams wore Robinson's No. 42.