After a 10-1 stretch that pushed them 12 games over .500, the Diamondbacks (31-22) have dropped three games in a row, matching their longest losing streak of the season. Both of their previous three-game skids -- April 12 through 15 and May 6-9 -- were followed by three-game winning streaks.
They have fallen into third place in the NL West -- 2 games behind division-leading Colorado -- despite having the sixth best record in the major leagues.
The biggest overriding concern continues to be the lack of consistent offensive production on the road. They are scoring just 3.5 runs per game on the road with a .222 collective batting average, compared with 6.0 and .295 at home. On the current road trip -- five games down, six to go -- Chris Herrmann is 0 for 10, Yasmany Tomas 1 for 11 and Paul Goldschmidt 2 for 15.
The Pirates (24-28) have won four of their last six but remain last in the jumbled NL Central -- 3 ½ games behind first-place Milwaukee.
D-backs starting pitcher Robbie Ray (4-3, 3.45 ERA)
While the D-backs' offense has struggled on the road, Robbie Ray has been the great equalizer. He is 3-1 with an 0.81 ERA and 43 strikeouts over 33 1/3 innings when pitching away from Chase Field, compared with 1-2 and 6.75 at home.
"I don't know anything about it," he said when asked to explain his success on the road. "All I can say is I'm going out there every five days trying to do the same thing."
Ray has not had any success in Pittsburgh, however, with an 0-2 record and 5.73 ERA at PNC Park in two starts. He lasted only four innings in a no-decision against the Pirates in Phoenix on May 14 -- surrendering home runs to Josh Bell and Andrew McCutchen.
But he hasn't given up a run since then. He pitched 7 2/3 innings scoreless innings and gave up two hits against San Diego on May 20, followed by 7 scoreless innings and two hits in Milwaukee last Thursday. He struck out 15 and walked three in the two gems.
"I'm starting to feel good about where I am mechanically, feel good about my pitches," he said. "I'm feeling confident. Everything's starting to flow together a lot better."
Richard MacksonRichard Mackson-USA TODAY Sports
Pirates starting pitcher Ivan Nova (5-3, 2.85 ERA)
Nova has worked six innings or more in all 10 of his starts and completed at least seven innings five times. He got the win against Atlanta in his most recent outing -- a 9-4 victory -- but it was not one of his more effective outings. He yielded 10 hits and four runs over 8 1/3 innings while striking out only one.
"I'm still a firm believer that a guy that can go out and give you seven innings is a great guy to have on the staff," Pirates manager Clint Hurdle said. "We're very happy that we've got Nova here, the work that he's done."
Nova is 1-0 with a 4.09 ERA in two career starts against the Diamondbacks. He matched up against Ray at Chase Field on May 14, but neither was involved in the decision. Nova gave up nine hits and three runs over six innings in what would turn out to be a 6-4, 10-inning for the Pirates.
Jason GetzJason Getz-USA TODAY Sports
The Pirates have struggled offensively -- ranking 24th in the majors in batting average (.239) and 27th in home runs (49) -- but they are showing some signs of life recently.
Shortstop Jordy Mercer, who had three hits in Monday's 4-3 win, is 15 for his last 31 at-bats, lifting his average to .254. Center fielder and former MVP Andrew McCutchen is hitting just .215 on the season, but he belted the game-winning home run on Monday and has a five-game hitting streak -- 6 for 16 with 2 home runs, four runs and four RBI.
Rookie first baseman Josh Bell is hitting just .232 but leads the team with nine homers and 24 RBI.