Tom Browning pitched a five-hitter for his first major league shutout and Dave Parker homered for the third consecutive game as Cincinnati won in Pittsburgh.
Player-manager Pete Rose's two-run double keyed a three-run Cincinnati fourth inning against loser Mike Bielecki (1-3) as the Reds remained unbeaten in four games on their current road trip. The Reds have won eight of their last 11.
Browning (4-2) struck out five and walked two.
Parker, getting his second three-hit game in as many nights against his former teammates, doubled in the third and came home on Alan Knicely's two-out single.
In the fourth, Ron Oester reached on a force play and Eddie Milner walked before Rose hit a double into right-center field. Parker was intentionally walked and Knicely hit his second RBI single to make it 4-0.
Parker, who has a 10-game hitting streak, hit his seventh homer of the season over the right field wall in the sixth.
The loss was the Pirates' ninth in their last 12 games and dropped their National League-worst record to 10-23.
Rose had two hits, giving him 4,128 for his career, 63 behind all-time major league leader Ty Cobb. Rose also scored one run, putting him one behind Hank Aaron's National League record of 2,107.