Updated

The Chicago Cubs head to the middle portion of their three- game series against the New York Mets without a key part to their lineup.

David DeJesus left Friday's 6-3 win with a right shoulder strain. In the bottom of the third, he went after a triple by Juan Lagares but the ball dropped out of his glove and his shoulder collided hard against the center field wall.

DeJesus writhed in pain as he was checked by team trainers but was able to leave the game under his own power. He was replaced by Ryan Sweeney.

"He had a huge hit for us then made a gutsy play out there," said Chicago manager Dale Sveum about DeJesus. "He paid for it in the end and almost made a huge catch. Hopefully it's nothing major and he'll only be out a couple weeks."

DeJesus, who is expected to go on the disabled list, is hitting .260 with six homers and 21 RBI in 59 contests this season.

Scott Feldman will try to hold the Mets in check this afternoon. Feldman gave up a season high-tying five earned runs in his last start Monday against the Reds in a loss. He's 1-1 with a 4.63 ERA in two starts when facing the Mets.

Jonathon Niese, who has just one victory in his last nine starts, takes the ball for the Mets. The lefty is coming off a pair of no-decisions, most recently Sunday against Miami as he gave up eight hits and three runs -- two earned -- over 6 2/3 innings.

Niese hasn't given up a homer in his last four starts and only five long balls this season. He's 2-3 with a 5.61 ERA in six games against the Cubs.

Last night, Edwin Jackson pitched six innings of one-run baseball. Jackson (3-8) gave up five hits and three walks while striking out seven. He earned consecutive wins for the first time since Aug. 30-Sept. 4, 2012. Kevin Gregg pitched a flawless ninth to notch his eighth save.

DeJesus delivered a three-run triple and Nate Schierholtz had a solo home run, while Luis Valbuena and Darwin Barney contributed an RBI apiece for the Cubs.

Daniel Murphy drove in two runs and Lucas Duda had an RBI for the Mets, who have lost nine of their last 11 games.

Shaun Marcum (0-8), who tossed eight innings of relief on Saturday against the Marlins, got the start for the Mets. He pitched 5 2/3 innings, allowing all six runs on seven hits and a walk. He is the first Mets pitcher to start a season 0-8 since John Franco in 1998.

"I think Shaun is a professional," said Mets manager Terry Collins. "He knows you got to go and get the job done. He's pitched very well but he was off to a very bad start. You make a couple of bad pitches and it's going to hurt you."

The Mets won two of three in Chicago from May 17-19.