PHOENIX -- It's been a mystery for the D-backs as to why right-hander Slade Cecconi has such great success the first time through an opposing lineup but struggles the second time through.

In 2023, Cecconi held opponents to a .177 batting average and .575 OPS the first time through the order, but it ballooned to .382 and .618 the second time.

This year, he's been even more dominant the first time through, with opponents hitting just .029 with a .084 OPS, but he's struggled even more the second time through, allowing a .355 batting average and 1.283 OPS.

This year's numbers were before his start Tuesday night against the Reds when he held Cincinnati hitless the first time through the order but allowed three runs the second time through and another three the third time around.

It added up to a 6-2 loss to the Reds at Chase Field and a very frustrated Cecconi.

On the bright side, though, Cecconi thinks he finally has a handle on what could be causing the disparity.

"When I find myself getting hit is when I find myself looking to place the ball and I'll usually maybe take a mile an hour or two off a pitch to try to execute it," Cecconi said. "And I'm learning that can't happen. That's not going to play at this level. The better thing to do is always to throw my best stuff and trust that me throwing my best stuff is always going to be better than me trying to place the baseball."

Cecconi usually comes out of the gate firing on all cylinders like he did Tuesday with a four-seam fastball touching 95 mph.

But the second time through, when he falls behind in the count, he focuses more on location and not on just letting the ball go. When that happens, the fastball doesn't have the same velocity, but more importantly, it doesn't have the same finish at the end of the pitch, making it easier to hit.

"A lot of our guys were just attacking that heater and we weren't missing it," said Reds outfielder Will Benson, who homered off Cecconi. "That's kind of why we had success today."

The D-backs have tried to figure out exactly what was causing the issue with Cecconi for some time now.

"It's been something that has been on my mind since I've known Slade," D-backs manager Torey Lovullo said. "But we're gonna figure it out. We're gonna try to get to the bottom of it."

At first, the D-backs thought it might be a conditioning issue, so they worked on that side of things. But when he faced his final hitter of the night, Jonathan India, Cecconi threw his hardest pitch of the night, a 96.6 mph fastball.

So, there was still plenty left in the tank.

They also thought it was a matter of his secondary pitches, so he worked hard to improve those. His slider, which he's thrown harder this year, has been a plus pitch for him.

Maybe they've finally found the answer and a frustrated Cecconi seems determined to make the necessary mental change.

"It's not a conditioning thing," Cecconi said. "It's an intent thing, and it's a mental thing. And, you know, as unfortunate as today was, I'm looking to use today as the day I take the mental leap. Now that I'm seeing the continued reoccurrence of that happening, I think it's more than enough for me to put my foot down and say this is enough. I'm not gonna let this happen again."