PHOENIX -- If there was one commonality between the Arizona Diamondbacks' starting pitchers coming into the 2015 season, it was that nobody knew what to expect from them.
Fifteen games in, that still holds true -- at least on a start-to-start basis. But the Diamondbacks have a lot better read on what the five diverse pitchers filling out their rotation have to offer and what they need to do to be successful.
Of late, it's been mostly good. The D-backs' starters have compiled a 1.88 ERA in their last seven games, allowing 10 earned runs in 48 innings. This comes after a rough start to the season in which the starters consistenly struggled to go deep into games, and the coaching staff feared the wear and tear would damage the bullpen.
"It's usually contagious is what it is," pitching coach Mike Harkey said of the recent success. "One guys throws five and two-thirds, the other guy wants to go six innings. The other guy throws six innings, another guy wants to go seven innings. Guys have been feeding off each other, which is really good, and you know what? Their fastball command as a staff has been a lot better."
By style, the group appears fairly similar. The D-backs starters don't have the stuff to rank at the top of the strikeout charts (25th in the majors with 6.13 strikeouts per nine innings), so they have attempted to rely on a solid infield defense gobbling up a steady diet of groundballs. With the only true power arms among the group belonging to Rubby De La Rosa and Archie Bradley, the D-backs are a change-up happy staff that ranks first in the majors by using the pitch 24.2 percent of the time, according to fangraphs.com.
"It (the change-up) just happens to be three of our starters' main pitch in Chase Anderson, (Jeremy) Hellickson and (Josh) Collmenter," Harkey said. "Even with Rubby, his second best is his change-up."
The fifth member in the rotation, Bradley, began his career by outpitching aces Clayton Kershaw and Madison Bumgarner, and his 1.45 ERA stands as the best start for Diamondback pitcher in the first three games of his career.
The de-facto ace of the staff is Collmenter, who struggled in his first two starts before delivering the team's most impressive start of the season in San Francisco last week -- the first complete-game shutout in the major leagues this season.
When the rotation circled back to Bradley on Wednesday, he endured his first serious struggles. His command deserted him in the first inning, so much so that he heard the bullpen phone ringing as reliever Andrew Chafin warmed up. Bradley responded by grinding out five more innings on 55 pitches to earn the win.
"I still didn't feel comfortable the whole night," he said. "I think that's what kept me in the game was the curveball. I was able to drop it in and keep them off from just sitting on the fastball."
So do we sense a theme through a 8-7 start? Bradley's outing was a microcosm of where this staff finds itself. The pitchers are still growing into the most significant roles in their respective careers, but in the past week they have flashed their potential to overachieve by the outsiders' standards.
"I think that they talk to each other and they know how to attack a team," catcher Tuffy Gosewisch said. "I think that as they get more comfortable, and the staff as a whole gets more comfortable working with me, we'll be able to better gameplan."
It's likely too early to say we know much about this staff. But perhaps the first 15 games have provided a better understanding of its floor and ceiling.
Collmenter: Manager Chip Hale has said he couldn't care less about the lack of velocity on Collmenter's fastball. Harkey went a step further in describing what he liked in Collmenter's 9-0 complete game shutout in San Francisco this past week. "He got a lot of his movement back that he didn't have before. He wasn't overthrowing. I think his average velocity first six innings was like 85 miles per hour. That's usually where he's best, right in there. Any harder than that, his ball tends to get up in the zone."
De La Rosa: Hovering around 93 mph, his fastball might be the hottest of the D-backs' starters, but he uses it the least (52 percent of the time). "I've seen him battle," Harkey said. "He's been able to keep himself out of some really big innings. He's still a work-in-progress. He has three-plus pitches (fastball, slider and change-up), but he has to learn to put them in the right sequences."
Hellickson: The D-backs never seem to worry about the 2011 AL Rookie of the Year who, like Collmenter, zeroed in on his command in his most recent start. "He's been around enough, he's pitched to enough good hitters to know he needs to get more innings under his belt, so he can build confidence. He's starting to get a little bit better with his fastball command and controlling counts, which is huge for him," Harkey said.
Anderson: Anderson has quietly been solid in his last two starts, even though they ended in losses for Arizona. "Just the guys I had last year, Chase Andersons, the Archie Bradleys, that have gained a year of maturity. They've gained a little bit more confidence. It helps when they go out there their second time through," Harkey said.
Bradley: Gosewisch offered some insight on Bradley's fastball: "He's got a bit of late life. It probably plays a tick or two harder than it says on the gun. And he's got a quality curve ball. We try to mix up the change-up when we can."
"A lot of times, when you see guys from the other side, you don't see their hickies -- what we call them -- the little things he doesn't do well. I'm not seeing anything. No hickies."
- - Chip Hale on if first baseman Paul Goldschmidt has any flaws.
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