Nick Piecoro

azcentral sports

LOS ANGELES – For most of the summer, while the Diamondbacks’ rotation has struggled through a disappointing year, the club has at least been able to point to its new ace, Zack Greinke, as a sort of beacon of hope.

He was hit hard for much of April, but Greinke bounced back and pitched well for two months, giving the Diamondbacks reason to feel good about the $206.5 million investment they made in him.

But his struggles have resurfaced in recent weeks, and after getting dismantled by the Dodgers on Monday night, serving up five home runs in 4 2/3 innings, Greinke’s ERA sits at 4.54, which ranks 60th out of 79 qualified starting pitchers in the major leagues.

His results not only have contributed to the Diamondbacks’ disappointing season – they entered Tuesday on pace for 93 losses – they raise questions about the team’s ability to contend in the coming years.

Diamondbacks Chief Baseball Officer Tony La Russa continues to believe his team can play “dramatically” better next season, but as it stands the club will be heading into 2017 needing enormous improvements from every member of its starting rotation.

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Greinke’s ERA is nearly twice as high as it was over the past three seasons (2.30), and he will enter next season at age 33.

No. 2 starter Shelby Miller, who had a solid return from the minors last week in San Francisco, was hammered on Tuesday, giving up five runs (four earned) in 4 1/3 innings against the Dodgers. His ERA is 6.89, more than twice what it was in his career (3.22) entering this year.

And left-hander Patrick Corbin, who began the year as the No. 3 starter, has a 5.61 ERA, which is nearly two runs above his career mark prior to this season. He was sent to the bullpen last month, and while the team still seems to view him as a starter next year, manager Chip Hale said the club has not had discussions about getting him back into the rotation this season.

Robbie Ray, Archie Bradley and Braden Shipley have ERAs of 4.46 or higher, while Rubby De La Rosa’s is at 4.15, but he missed more than three months with elbow problems.

As a whole, the Diamondbacks’ rotation has a 5.23 ERA, the worst mark in the National League. That’s nearly a run worse than last year’s rotation, which had a 4.37 ERA. The bullpen hasn’t been much better, posting a major league worst 5.19 ERA.

MORE: Greinke a 'little bit' off in loss to Dodgers

La Russa does not seem to think the sort of improvements the Diamondbacks will need are out of the realm of possibility, and he says he buys into the character of his players to be able to buy into the work necessary to get there. And he sees room to improve in every area, not just the pitching staff.

“I just talked to a friend in the military, and he said, ‘You learn more from failure and adversity,’ which is the truth,” La Russa said on Tuesday night. “I think we’ve got good character and good talent, and if they have a good attitude about, ‘Let’s learn from this,’ then it can be dramatically better.

“I think this is the best kind of test because each player – and, I mean, everybody, each of us upstairs and everybody on the coaching staff – is going to make a personal assessment of, ‘OK, what could I have done better?’ And the quality of the response will dictate if these guys are what they think they are.”

It remains unclear if La Russa and the rest of his baseball operations staff, including General Manager Dave Stewart, will return next year. Diamondbacks CEO Derrick Hall said last month the group was being “evaluated.”

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La Russa does not appear to have second thoughts about giving Greinke a six-year deal that paid him a record $34.4 million per year despite the inauspicious start.

“I think he’s exactly what our rotation needed,” La Russa said. “We needed the veteran number one. He’s a veteran number one. He can really help with, and he already has, showing guys the art of pitching.”

And while the club might have had a chance to extricate itself from Greinke’s deal when the Dodgers called to ask about his availability last week, La Russa sees Greinke as a part of a potential turnaround next year.

“I think you can ask Dave, but there wasn’t one serious conversation about him with the Dodgers,” La Russa said, referring to Stewart.

“I think this winter we’re going to be asked a lot about him and every one of our starters . It’s already happened. Our young guys are really attractive. And Shelby is going to be attractive. They think we’ll be down on him. And Greinke’s going to be attractive to guys who can afford him because they’ll think we can’t afford him.”

Reach Piecoro at (602) 444-8680 or nick.piecoro@arizonarepublic.com. Follow him on Twitter @nickpiecoro.

Wednesday’s game

Diamondbacks at Dodgers

When: 7:10 p.m.

Where: Dodger Stadium, Los Angeles.

Pitchers: Diamondbacks LHP Robbie Ray (7-12, 4.46) vs. Dodgers RHP Brock Stewart (0-2, 7.94).

TV/Radio: FSAZ/KMVP-FM (98.7), KSUN-AM (1400).

Ray endured a rough fifth inning at Coors Field, where the Rockies scored six times by collecting seven hits in the span of eight batters. … Ray had been throwing well prior to that start, posting a 1.50 ERA in 24 innings in four previous outings. … He shut out the Dodgers, who have struggled against left-handed pitchers, over seven innings when he faced them in July. … Stewart was hammered in his first two big league starts, one in June and the other in early August, but after a solid three-inning relief appearance on Aug. 14 he was given another start last week against the Cubs and threw well, striking out eight in five scoreless innings. … Stewart averages 93.4 mph with his fastball and also has a change-up and a slider.

Coming up

Thursday: Off.

Friday: At Chase Field, 6:40 p.m., Diamondbacks RHP Braden Shipley (3-3, 4.94) vs. Giants LHP Madison Bumgarner (14-8, 2.51).

Saturday: At Chase Field, 5:10 p.m., Diamondbacks RHP Archie Bradley (6-8, 4.85) vs. Giants RHP Johnny Cueto (14-5, 2.92).

Sunday: At Chase Field, 1:10 p.m., Diamondbacks RHP Zack Greinke (12-5, 4.54) vs. Giants LHP Matt Moore (9-11, 4.14).