Greg Gross doubled and scored the first run then singled to break a 1-1 tie in the seventh inning last night in Philadelphia to lead the Phillies to a 2-1 victory over the Chicago Cubs behind the four-hit pitching of Steve Carlton.

The triumph lifted the Phillies within a half-game of first-place Pittsburgh, which was idle, in the National League East.

Carlton (10-11) struck out 12 in notching his first victory since July 4. The victory was Carlton's 295th lifetime and his all-time strikeout total is 3,609, 13 ahead of Houston's Nolan Ryan. It also marked the 74th time in his career that Carlton has fanned 10 or more in a game.

Bill Campbell (3-7), in relief of Ferguson Jenkins, took the loss.

Gross opened the first inning with a double, took third on an error and scored on Mike Schmidt's sacrifice fly. The Cubs tie the score in the second when Jody Davis drew a one-out walk, moved to second on a balk by Carlton and scored when Joe Carter singled for his first major-league hit.

Bo Diaz doubled to open the Phillies' seventh, was sacrificed to third and scored on Gross' two-out single.

It was a rare start for outfielder Gross, who is batting .319. "He's one of the most underrated players in the league," Manager Paul Owens said. "He'll be playing more. We'll find a spot for him."

Carlton was the batter just before Gross' game-winning hit. He struck out. "No way I take Steve out in that situation," said Owens. "This was his best game since early in the year."