Chicago, IL -- (Sports Network) - Aramis Ramirez hit a go-ahead grand slam as part of a five-run eighth inning, as the Chicago Cubs shocked the Philadelphia Phillies with a 6-4 comeback win in the opener of a four-game set from Wrigley Field.

Ryan Madson entered in the eighth with a 4-1 lead but allowed a pinch-hit, leadoff homer to Mike Fontenot. Alfonso Soriano doubled and Ryan Theriot followed with a single forcing Madson from the game in favor of Chad Durbin (5-3), who walked Derrek Lee to load the bases setting up Ramirez' blast.

"He's an RBI guy. He likes to be up there in big situations," Cubs manager Lou Piniella said of Ramirez. "He knows how to hit and he rises to the occasion. He takes it to a little different level. The good ones really do that."

Chicago's surge of offense made a winner out of Bob Howry (6-4), who pitched a scoreless eighth, and Kerry Wood got his 28th save of the season by working around a leadoff single in the ninth. Mark DeRosa's RBI triple in the fifth provided the Cubs' other run.

Chicago has now won six in a row and seven of eight to open up a 6 1/2 game lead in the NL Central over Milwaukee. Cubs starter Ryan Dempster was touched for eight hits and four runs while walking four and fanning seven in the no- decision.

"We're playing good baseball, and we're focused. We're playing with confidence," Piniella said. "It's a credit to our kids -- they don't back off and they keep coming at you. Good things happen when you play nine innings of baseball."

The Phillies fell to a full game back of the New York Mets in the NL East with their second straight loss. Cole Hamels pitched brilliantly as the starter, holding the Cubs to one run on five hits while striking out six without walking a batter through seven innings.

Chase Utley had three hits while knocking in a run and scoring once. Carlos Ruiz, Shane Victorino and Jimmy Rollins drove in the other runs for Philadelphia.

The Phillies took an early lead in the first on an RBI single from Victorino that scored Utley, who doubled with one down. Chicago tied things up at one in the fifth when Kosuke Fukudome singled and scored on DeRosa's triple.

A three-run sixth from Philadelphia gave the club a 4-1 lead. Jayson Werth doubled to lead off the frame and Pedro Feliz drew a walk before Ruiz plated a run with a single to left. Hamels moved the runners into scoring position with a sac bunt and Rollins came through with a sac fly. Utley followed by ripping an RBI single to left.

Game Notes

Philadelphia took two of three contests from Chicago at Citizens Bank Park April 11-13 and are 15-9 against the Cubs since the start of the 2005 campaign, including a 7-5 mark at Wrigley Field...Philadelphia optioned pitcher Andrew Carpenter to Double-A Reading and recalled pitcher Fabio Castro from Triple-A Lehigh Valley Thursday...The Phillies started an important stretch of 10 straight road contests Thursday that will eventually see them end in New York for a three-game set with the Mets from September 5-7...DeRosa is riding a 10-game hitting streak.