Kevin Frandsen had two hits and scored two runs after entering in the sixth, helping Philadelphia bounce back from Thursday's 11-3 loss to the New York Mets. Chase Utley added a key two-run triple.
The Phillies improved to 9-6 since Sandberg was promoted to interim manager when Charlie Manuel was fired on Aug. 16. The Hall of Fame second baseman spent most of his playing career with the Cubs and was cheered all day long in his first trip to Chicago since he was elevated to the top spot in Philadelphia.
Anthony Rizzo and Nate Schierholtz homered for the Cubs, who blew a 5-0 lead. Starlin Castro had two hits and two RBIs in Chicago's fourth loss in five games.
Roger Bernadina used his speed to set up Young's winning hit. He was hit by a pitch from Kevin Gregg (2-4) with one out, swiped second and raced home when Young's blooper landed in front of Schierholtz in right field.
B.J. Rosenberg (1-0) pitched a scoreless inning for the win and Jonathan Papelbon got three outs for his 23rd save. Utley made a great diving stop and throw on Schierholtz's grounder to second to end the game.
Philadelphia won for the third time in four games this season against last-place Chicago, but left fielder Domonic Brown had to leave early due to a sore right Achilles. The team said he's day to day.
The Cubs built a 5-0 lead against Roy Halladay, putting Jeff Samardzija in position for his third consecutive victory. The right-hander was 2-0 with a 1.59 ERA in his previous two starts.
Samardzija retired 11 in a row and was working on a two-hitter before Frandsen led off the sixth with a sinking liner that got past center fielder Junior Lake's diving attempt and rolled to the wall for a pinch-hit triple. That seemed to wake up the Phillies, who got right back in the game with a four-run rally.
Young drove in Frandsen with a base hit to right, and Utley's big swing trimmed Chicago's lead to 5-3. Utley came home on Domonic Brown's groundout.
Samardzija finally got out of the inning when Darin Ruf grounded into a double play, but he was unable to hold onto the lead. Frandsen lined an 0-1 pitch into the bleachers in left with two out in the seventh, tying it at 5.
James Russell came on with two on and two out and got Utley to fly out to left, closing Samardzija's line. He gave up eight hits and walked two in his worst start since he lasted just 3 1-3 innings in a 12-1 loss at Philadelphia on Aug. 8.
Chicago had a chance to go back in front in the bottom half, but Dioner Navarro was thrown out when he tried to score from second on Darnell McDonald's pinch-hit single. John Mayberry's throw from right field bounced several times and still beat the lumbering catcher to the plate, drawing groans from the crowd of 27,753.
Halladay made his second start since he had right shoulder surgery in May. The two-time Cy Young Award winner pitched six effective innings in a 9-5 victory over Arizona on Sunday, but he struggled right from the beginning against the Cubs, perhaps bothered by the muggy conditions.
Rizzo connected for his 21st homer in the first inning, and Halladay hit consecutive batters in the second. He threw a ball behind Lake at one point, drawing a stare from the rookie outfielder.
Chicago used Halladay's wildness and a misplay by Bernardina to score three times in the fourth. After Schierholtz led off with his 20th homer, Bernardina lost Donnie Murphy's routine fly ball to center in the sun, letting it fall for a double. Brian Bogusevic then walked to put runners on first and second.
Castro cashed in with two out, lining a two-run double into the gap in right-center to give the Cubs a 4-0 lead.
Bogusevic added a run-scoring single on Halladay's final pitch of the game. The right-hander allowed five runs and seven hits with two walks while throwing only 77 pitches.