Hero: Rookie reliever Marcos Mateo had his best of his eight major league outings, striking out all three hitters he faced, in the bottom of the eighth.
Goat: Tom Gorzelanny (7-8) was decent in his two previous starts against the Reds, but on Friday, not so much. The left-hander was ponded for six runs - all earned - on seven hits (including three homers) in five innings. He walked two and struck out one.
"Nothing worked for me today," Gorzelanny said. "I made bad pitches, got behind guys. A bad outing, a real bad outing."
Key Play: Jay Bruce hit his third career home run off Gorzelanny - and his second of three in Friday's game in the fifth inning with two aboard - to give Cincinnati a commanding 5-1 lead.
Comments: In winning for the 11th time in 14 games against the Cubs (54-75) this season, the first-place Reds (74-54) maintained a four-game lead over second-place St. Louis in the NL Central.
Bruce became the 26th Reds player to hit three home runs in a game and was the first Cincinnati player to accomplish the feat since Drew Stubbs did it at Wrigley Field on July 4.
Tyler Colvin, who had an RBI double in the fourth inning off Cincinnati starter Johnny Cueto, has hit safely and collected at least one RBI in each of his last four starts.
Cueto (12-4) allowed six hits, struck out eight, and walked none in eight innings.
Starlin Castro, who went 0-for-4 and is now hitting .311, was held hitless for just the ninth time in 40 games since the All-Star break.
Left-hander Scott Maine, who pitched an inning Friday after being called up from Triple-A Iowa on Tuesday, became the 16th rookie to play for the Cubs this season and the 10th to make his big league debut.
Next: Randy Wells (5-12, 4.56 ERA), who is 1-1 with a 2.45 ERA in two previous starts against the Reds this season, starts on Saturday (CSN, 6:10 p.m.). Wells is 0-5 with a 3.62 ERA in August.
The Reds will counter with Bronson Arroyo (14-7, 3.82) who has won both of his starts against the Cubs this season with 13 shutout innings. The 33-year-old right-hander is 6-3 with a 3.09 ERA in 11 career outings (10 starts) against the North Siders. Arroyo, who won his 100th career game in his last start, has worked seven or more innings in 16 of his 26 starts this season and in five of his last six.