PHOENIX -- Paul Goldschmidt is in his worst slump of the season, and things didn't get any better Saturday night.
Goldschmidt was 0 for 4 and left three runners in scoring position in Arizona's 4-1 loss to the Cincinnati Reds on a night the Diamondbacks retired Hall of Famer Randy Johnson's No. 51.
"He can't always be the guy that saves us," Arizona manager Chip Hale said of Goldschmidt. "We always count on him to be that guy but it is not that easy to do all the time. They are pitching him pretty well. He obviously didn't get the hits tonight but we always want him up in those situations and we will take our chances."
Keyvius Sampson earned his first major league victory and Cincinnati hit three home runs.
"He was using his fastball a lot," Hale said. "His breaking ball, he was mixing it in to keep guys off balance but basically he was throwing and beating us with his fastball. You really can't say that too often about our club."
All the Cincinnati runs came on homers by Eugenio Suarez, Brandon Phillips and Marlon Byrd, whose solo shot in the ninth was his 150th career home run.
The Reds broke a 30-inning scoreless streak.
"Three homers, that will do something to end the drought," manager Bryan Price said.
Sampson (1-1) gave up a first-inning run but the Diamondbacks never scored again. He went six innings and allowed four hits, struck out four and walked three.
Robbie Ray (3-7) pitched six innings for Arizona, allowing three runs and five hits. He matched his career high with eight strikeouts and walked one but fell to 0-3 in his last five starts.
"I felt like I pitched well," Ray said. "It is two pitches that got me tonight. If I could take those back I would. For the most part I threw well and gave my team a chance to win. `'
Aroldis Chapman, hitting 103 mph on the Chase Field radar gun, threw a scoreless ninth for his 24th save in 25 opportunities.
Sampson lost his only other start, despite a solid outing in Pittsburgh's 3-0 win over the Reds last Sunday. He pitched a perfect inning of relief in his major league debut on July 30.
The Reds, shut out in their previous two games, scored all three runs off Ray with two outs. Suarez hit a two-run homer in the fourth, and Phillips added a solo shot in the fifth.
In the fourth, Byrd hit a bloop double down the left-field line and, on the next pitch, Suarez homered to put the Reds up 2-1. Phillips lined a 3-2 pitch just over the left-field wall to make it 3-1.
Arizona scored in the first when A.J. Pollock doubled to right and scored on David Peralta's single.
The Diamondbacks had runners on first and second with one out in the fourth and again in the fifth. In the fourth, Sampson escaped the jam with consecutive flyouts to right by Aaron Hill and Nick Ahmed. Goldschmidt grounded into a double play to end the fifth.
Reds: RHP Anthony DeSclafani (7-7, 3.71 ERA) goes for his third consecutive win in the series finale Sunday.
Diamondbacks: LHP Patrick Corbin (2-3, 3.99) looks to bounce back from his worst start since coming back from Tommy John surgery. He gave up three runs in 1 1-3 innings at Washington on Tuesday.
