Edwin Jackson allowed two earned runs on eight hits and struck out five over five-plus innings.
The Cubs offense worked Reds’ starter Tony Cingrani deep into counts, with 32 pitches in the first inning and they chased him after five innings at 104 pitches.
Justin Ruggiano hit a RBI single to left to score Emilio Bonifacio in the first for a 1-0 lead before Mike Olt pulled the Cubs’ first home run down the left field foul pole for a 2-0 lead after the second. It was Olt’s third of the season.
With the bases loaded, Starlin Castro knocked in another run on a fielder’s choice in the third for a 3-0 lead.
The Cubs regained their three-run lead when Darwin Barney hit a home run – his first of the season – to left and Junior Lake added another with a RBI single to center to give the Cubs a 6-2 lead after the sixth.
Castillo put the Reds away in the bottom of the seventh with a two-run home run for a 8-4 lead. It was his third of the season.
Hector Rondon and Pedro Strop pitched the final two innings, shutting down Cincinnati to take game two of the series, 8-4. The Cubs will attempt to win their first series this season on Sunday afternoon.