Ryan Ludwick homered and drove in four, helping the Reds down the Padres, 6-4, on Wednesday.
Ludwick belted a two-run homer in the first inning, knocked in the go-ahead run in the fifth and added insurance with an RBI single in the seventh.
"We have to have somebody hot in the middle and that's what Ryan Ludwick is giving us now. He's driving in key runs, hitting home runs and running the bases," Reds manager Dusty Baker said.
Zack Cozart also hit a first-inning homer -- a leadoff shot -- for the Reds, who have taken two of three to start this four-game series and are a major league-best 16-3 since the All-Star break.
Bronson Arroyo (7-6) won his third straight start, allowing four runs on seven hits over six innings. He walked two and struck out one.
Jonathan Broxton, who was acquired from the Royals on Tuesday, tossed a 1-2-3 eighth in his Cincinnati debut and Aroldis Chapman worked around a two-out double in the ninth to lock down his 23rd save of the season.
Chase Headley had a first-inning, two-run homer for the Padres and later added an RBI single, which briefly put his team on top in the fourth.
Kip Wells (2-4) lasted 4 1/3 innings against his former team and was charged with five runs on five hits. He also singled and scored a run.
The Padres were coming off of a 15-11 July -- their first winning month of the season.
Wells, who pitched with the Reds in 2009, reached with a two-out line drive in the fourth and scored the tying run on back-to-back singles by Alexi Amarista and Will Venable.
Headley then plated Amarista with a base hit, making it 4-3, but the Reds battled back in the fifth.
Drew Stubbs singled and scored the tying run on Jay Bruce's one-out double down the right field line. Dale Thayer then relived Wells and recorded an out before Ludwick flared a sinking liner to right, making it 5-4.
The Reds are 13-3 since former NL MVP Joey Votto went down with a knee injury in late June and Ludwick has been essential, driving in 20 runs over that span. He is in the midst of a six-game hitting streak and a five-game RBI streak and is 7-for-15 with four home runs and 12 RBI over his last four contests.
"Ludwick, over the last three weeks has really done well," commented Padres manager Bud Black. "He's in a nice groove."
The Cincinnati bullpen was also key on Wednesday, as Sean Marshall relieved Arroyo with a perfect seventh and Chapman fanned Logan Forsythe after Carlos Quentin's ninth-inning double.
Chapman has converted 15 straight save opportunities and had recorded at least one strikeout in 47 of 48 appearances this season.
Reds second baseman Wilson Valdez left the game with a neck injury. He was replaced by Miguel Cairo in the fifth inning...Broxton was acquired from the Royals in exchange for minor leaguers pitchers Juan Carlos Sulbaran and Donnie Joseph...Earlier Wednesday, Reds catcher Devin Mesoraco received a three-game suspension and an undisclosed fine from Major League Baseball for making contact with an umpire.