A grand slam by Greg Brock, the third of his career and his second of the season, powered a five-run seventh inning as the Los Angeles Dodgers defeated the Braves, 10-4, completing a doubleheader sweep yesterday in Atlanta.

In the opener, Rick Honeycutt pitched a five-hitter in his first complete game of the year and Mariano Duncan batted in five runs to lead Los Angeles to a 10-1 victory.

The Dodgers are 11-3 against the Braves this year.

The score was tied at 4 in the seventh inning of the second game when the Dodgers loaded the bases on walks to Duncan and Enos Cabell and a single by Ken Landreaux against reliever Zane Smith (6-9).

Steve Shields replaced Smith and walked Mike Marshall, forcing in the lead run, then Brock hit his 19th homer.

Mike Scioscia hit his seventh homer in the ninth inning.

In the opener, Honeycutt (8-12), who had lost six of his last eight decisons, contributed to a five-run second inning with an RBI single. He struck out two and walked three.

Duncan drove in two in the second with a single against Pascual Perez (1-10) and knocked in two more in the third with a triple off Jeff Dedmon.

Honeycutt's bases-loaded single with one out in the second scored Bill Madlock. Duncan followed with his two-run hit. After an out and a walk, Dedmon replaced Perez and yielded a two-run single to Brock.

Atlanta made it 7-1 in the third when Brad Komminsk led off with a walk and came around on a single by Bruce Benedict, a sacrifice by Dedmon and a sacrifice fly by Rafael Ramirez.