WHAT IT MEANS: The letdown that Terry Collins feared might occur after the Subway Series seemed to materialize.

Facing the team with MLB's worst record, the Mets mustered only six hits -- including two apiece by Ronny Cedeño and Mike Nickeas -- and lost to the Chicago Cubs, 6-1, Monday night at Wrigley Field in a game that got out of hand with a three-error seventh.

Ike Davis' two-out homer in the ninth avoided the shutout.

Johan Santana mostly dominated Chicago, but he issued a two-out walk to Geovany Soto in the fourth, followed by a two-run homer to left field by Joe Mather into a stiff wind as the Cubs grabbed a 2-0 lead.

Santana completed his outing by leaving the bases loaded in the sixth, after an intentional walk to Mather, by coaxing a groundout from Luis Valbuena.

The Mets combusted with three errors in the seventh, which resulted in four unearned runs.

With Jon Rauch pitching, David Wright dropped a pop fly from Adrian Cardenas by the plate for a three-base error. Lucas Duda’s drop of a shallow fly ball in right field off the bat of Darwin Barney with one out resulted in another three-base error. And Cedeño, playing on the infield grass trying to cut down Barney at the plate, could not handle Starlin Castro’s grounder, resulting in the second unearned run scoring in the inning and a 4-0 Cubs lead.

Ramon Ramirez then made his first appearance since returning from the DL and allowed both runners inherited from Rauch to score.

DEBUTANT: Left-hander Justin Hampson, promoted from Triple-A Buffalo to pair with Tim Byrdak in the bullpen, made his Mets debut with a scoreless eighth despite surrendering a two-out triple by Reed Johnson.

DOUBLE DISPLEASURE: The Mets had two-out doubles by Cedeño in the second inning and by Nickeas in the fifth against left-hander Travis Wood, but both were followed by inning-ending groundouts. Wright had the Mets’ third hit, a two-out single in the sixth that extended his hitting streak to 15 games. Cedeño added a one-out single in the seventh, but was stranded at second base when Justin Turner flied out as the pinch hitter for Santana.

WHAT’S NEXT: Dillon Gee (5-5, 4.27 ERA) opposes right-hander Randy Wells (1-2, 4.91) at 8:05 p.m. ET Tuesday.