Senzel and Ervin hit solo home runs, Luis Castillo pitched six effective innings and the Reds beat the St. Louis Cardinals 5-3 Sunday night to end a four-game losing streak and salvage a split of the teams' second doubleheader in two days.
"They grinded it out and I'm really happy for the team that we came out with a win in the last of the four when these guys have given everything they have for two days," Reds manager David Bell said.
"And again tonight that showed another example of that, when it could have gone the other way," he continued. "Guys are tired, really tired right now, and they grinded it out for a win."
Castillo (14-5) lasted six innings, giving up three runs and five hits with three walks. He struck out eight as the Reds' pitchers had 11 in the game.
Raisel Iglesias pitched a perfect ninth for his 28th save, a night after he blew an opportunity.
Castillo said it was important to him to help his team find a way to win.
"When you've lost three games you feel bad," he said through an interpreter. "The main thing is to go out there and compete and win one. That's what I was thinking about."
With the 4-3 win in the first game and the Chicago Cubs' 4-0 loss to Milwaukee, the Cardinals gained a half game in the NL Central to increase their division lead to three games. St. Louis has only lost two of its past 11 games and is 12-3 in its past 15.
Daniel Ponce de Leon (1-2) allowed four runs -- three earned -- and five hits with a walk, and a hit batter in four-plus innings in the night game. Called up earlier in the day when rosters expanded, he entered the fifth with a 3-2 lead but gave up Senzel's 12th homer to left center to start the inning. Joey Votto, who doubled off the Cardinals' starter, also scored in the inning as the Reds took a 4-3 lead.
Ervin's fifth homer of the season in the sixth capped the scoring. He finished a triple shy of the cycle.
The Cardinals Andrew Knizer hit his second homer of the season, a two-run shot that was part of a three-run third for St. Louis. Kolten Wong had three hits, including a triple, and an RBI.
"Yeah, that's a whirlwind of baseball and overall very, very satisfied and very pleased," Cardinals manager MIke Shildt said. "Proud, but not surprised, with how our guys competed."
In the first game, Harrison Bader continued his hit parade with a game-ending single to lift the Cardinals to the win.
"In that situation, I was aware of the infielders, but I wasn't paying attention to them," Bader said. "Because I'm just trying to get the ball in the air."
Bader is hitting .333 (12-for-36) with nine RBI in 12 games since being recalled from Triple-A Memphis.
Eugenio Suarez homered for the Reds, who have dropped four in a row. Suarez then left the second game after being hit by a pitch in the fifth inning.
Jose Martinez began the Cardinals' winning rally with a walk. Yadier Molinafollowed with a ground rule double to set the stage for Bader's hit.
Carlos Martinez (4-2) picked up the victory by striking out the side in the ninth on 13 pitches.
Cincinnati starter Tyler Mahle, who was added to the roster from Triple-A Louisville earlier in the day, gave up two runs, one earned, on two hits over 6 1/3 innings. He struck out five and did not walk a batter.
Suarez broke a 1-1 tie with a two-run shot in the third, his 40th homer of the season. He has a major-league leading 20 homers since the All-Star break.
The Cardinals played back-to-back doubleheaders for the first time since Aug. 20-21, 1998, at the New York Mets. St. Louis won both games on Saturday. Cincinnati played back-to-back doubleheaders for the first time since Sept 10-11, 1968.
Cincinnati Reds hitting coach Turner Ward was ejected in the top of the seventh in the second game.
With second baseman Freddy Galvis at the plate with one out, home plate umpire Bill Miller took of his mask and pointed in the Reds' dugout before tossing Ward. No reason was immediately given for the ejection, though both teams had grumbled about the strike zone all night.
Reds: Suarez spent only a few moments with the Reds trainers on the field before going back into the dugout, throwing his helmet to the ground in frustration. He was in a brace after the game and said he could grip, but have an MRI done Monday in Cincinnati.
Cardinals: C Matt Wieters suffered a calf injury on Saturday. He is listed as day-to-day. C Joe Hudsonwas added to the roster from Triple-A Memphis. ... OF Jose Martinez was activated from the 10-day IL and went 1 for 2 with a walk and hit by pitch in the second game.
Reds: RHP Anthony DeSclafani (9-7, 4.05) will face Philadelphia LHP Drew Smyly (2-6, 6.95) on Monday in the first of a four-game series in Cincinnati. DeSclafani has given up two earned in his last 18 innings over three starts.
Cardinals: RHP Adam Wainwright (9-9, 4.52) will face San Francisco RHP Tyler Beede (3-8, 5.56) in the first of a four-game set against the Giants in St. Louis. Wainwright is 6-7 with a 3.31 ERA in 16 career appearances against San Francisco.
Freelance writer Steve Overbey contributed to this report.
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