PHOENIX -- He had departed the game long before it was over and had a couple of hours to digest things, but D-backs right-hander Luke Weaver still had a hard time understanding what transpired.

Weaver took the mound Saturday night at Chase Field looking to build on the three-inning relief stint he had last time out against the Phillies. If he did that, he had a chance to lay claim to being the No. 5 starter in the rotation, something the D-backs had been searching for since Humberto Castellanos injured his elbow.

Weaver cruised through the first two innings, but things got wobbly in the third as the Twins plated six runs. Minnesota would score three more in the fourth to chase Weaver from what turned out as an 11-1 loss for Arizona.

"I think the first thing is it seems like it's hard to believe," Weaver explained. "You know, you walk away and you're past the point of frustration and you just kind of feel like shell-shocked. It was going really well, and I was making good pitches, getting quick outs [and] being efficient just like I wanted to do. And just a couple of balls there got through, some timely hitting and then [it] just became contagious. It's one of those ones where it's going to be tough to sleep tonight."

Weaver was told a couple of days before the season started that he was not going to make the starting rotation and instead would open the year in the bullpen. He appeared in relief on Opening Day and then was placed on the injured list with an elbow issue.

Removed from the IL last weekend in Philadelphia, Weaver looked good in his relief outing against the Phillies (3 IP, 1 ER, 4 K's) and so he became the latest pitcher to get a shot at filling Castellanos' spot in the rotation.

Whether he gets another opportunity the next time the spot rolls around remains to be seen.

"We're looking for somebody to step up," manager Torey Lovullo said. "This is an opportunity for a lot of starting pitching in our system. And I want somebody to step up and take that spot. We're not going to just hand it to people."

So where do they go from here with Weaver?

"I don't know that answer," Lovullo said. "We're going to talk about it. We do a really good job of exhausting a lot of different conversations about our team. And we'll figure that out. We're going to huddle up and talk about it as a staff, probably have some excellent baseball conversations."

Tyler Gilbert got the first crack at the spot in Cincinnati on the last road trip, but he allowed seven runs (six earned) in just 1 2/3 innings before being optioned back to Triple-A Reno.

The D-backs went with lefty Kyle Nelson as an opener against the Phillies before bringing in Weaver. His performance then warranted Saturday's start.

It's unclear as to what the D-backs will elect to do with Weaver moving forward.

For his part, Weaver is still trying to get comfortable with the mechanical changes he made during his injury rehab stint. They are ones the organization feels will give him a better chance to stay healthy in the future.

"There's no excuses and the results are [the] results," Weaver said. "But I have to understand that I've changed some things, and I'm trying to stay healthy and get out there and do what I know I can do. I have to trust them and believe that. And it's easy to look right now at that line and not believe in that. So, I sit here with a lot of mixed emotions, but I think I just have to sit there and just have some grace and just realize that's not who I am, that's not what I want to be. And [that] the ballclub deserves more than that."