SCOTTSDALE, Ariz. -- In the race for the D-backs’ No. 5 slot in the starting rotation, Ryne Nelson appears to have claimed pole position after his latest solid Cactus League outing Monday at Salt River Fields.

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Working alongside catcher Gabriel Moreno, Nelson deftly worked through 3 2/3 frames of action with his five-pitch mix in an eventual 6-5 D-backs loss. A hanging slider to Oakland’s Zack Gelof in the third inning kept him from a scoreless afternoon, but he once again pounded the strike zone and elicited some off-balance whiffs from A’s batters on his offspeed pitches.

Of the nine changeups Nelson threw, batters swung at five and whiffed on three. He even incorporated the offering -- utilized 97.1 percent of the time vs. left-handers last year -- once to a righty as something of a test run, an opportunity afforded by Spring Training.

“When the change is working, I feel really good out there,” Nelson said. “It gives me another weapon to throw at them and keep them off my fastball.”

Through four Cactus League starts, Nelson has worked to a 3.09 ERA but has most importantly limited his free passes to two across 11 2/3 innings. Both he and D-backs manager Torey Lovullo are encouraged by the progress he’s made as his pitch count has incrementally ramped up (66 pitches Monday).

“I thought Nelly threw the ball really well,” Lovullo said. “He looked like he had a little bit better depth or more swing-and-miss potential with the slider. Fastball [was] very aggressive. He was pitching a little bit, he just wasn't up there throwing -- he was sequencing.”

“I think for me it's more important to work on those things and to try and make myself better,” Nelson said of altering his mix. “And I think in turn, that helps me get guys out. I think they go hand in hand. You don't have to do one versus the other; if my pitches are better, I'm probably gonna get more outs.”

Big league lineup, big league velocity
Rolling out a one-through-nine that could look quite similar to what he hands to the umpire crew come Opening Day on March 28, Lovullo watched as his bats were held to just five hits against the A’s. Beyond the old axiom of pitchers being ahead of hitters at this stage of Spring Training play, Oakland boasted a considerable amount of firepower on the mound, starting with righty Joe Boyle.

The No. 10 A’s prospect, who is primarily a fastball/slider arm, averaged 98.3 mph with his heater and maxed out at 99.6. That top-tier velo was one-upped later on by Mason Miller (OAK No. 2) who averaged 100 mph and cranked it up as high as 101.7.

“I think our guys are prepped to get on the gas and turn it around,” Lovullo said. “They looked good. They made some quality pitches and they have young, healthy arms and they were getting after it and they beat us today. So I don't think the velocity throws us off, it's just a matter of getting the pitch we're looking for.”

Despite a late flurry of walks and hit batsmen that nearly resulted in a roaring ninth inning comeback, the D-backs’ bats were mostly held in check while the starting nine was a part of the lineup; of the three hits from that group, just Geraldo Perdomo’s fifth-inning single registered as hard hit.

“This team, I feel, has less of the vulnerabilities than we had last year,” Lovullo said. “So I think we're in a really good spot, but we’ve got some work to do to still get to that point.

“We're gonna get hit in the face, there's no doubt about it. We're gonna get slugged in the face at some point in time during the season. It's just baseball and sports and you can't go 162-0. I wanna know what this team is gonna look like when it gets socked in the face. And I'm feeling very good about it being able to stand up.”