MILWAUKEE -- It was almost lost in the shuffle amid the flurry of moves they made on Saturday, but seeing the letters T-B-A in place of a starter for Wednesday in Atlanta serves as a reminder: The Pirates have a hole in their rotation.

It might be filled by top prospect Mitch Keller, but they’re not yet ready to say for certain.

The Pirates on Saturday designated right-hander Nick Kingham for assignment and placed Rookie Davis, who started Friday in Kingham’s spot, on the 10-day injured list with a right middle finger blister. Injured starter Jameson Taillon (right elbow flexor strain) still isn’t throwing, and Trevor Williams (right side strain) will need at least one Minor League rehabilitation start before he’s ready to rejoin the rotation.

So, who’s going to pitch on Wednesday at SunTrust Park? Keller made his case by striking out 13 hitters in five innings for Triple-A Indianapolis on Friday night.

“We’ll look externally. He’s certainly in the conversation for us as we go forward,” general manager Neal Huntington said on Sunday. “And ideally, the next time he comes up, he doesn’t go back. Are we to that point yet? That becomes the question.”

The Bucs sent Keller back to Triple-A the day after his Major League debut in Cincinnati, which included a six-run first inning followed by three scoreless frames. He put together a quality start for Indianapolis in his return to the Minors, then he racked up a career-high 13 strikeouts against Toledo.

Huntington noted that Keller loaded the bases with nobody out in the first inning on Friday before recording 12 straight outs via strikeout.

“Need to make sure we don’t do that [in the first inning] his next start up here,” Huntington said. “Certainly showed the dominant ability and the reasons why we’re excited about him after that.”

With the Pirates’ pitching staff struggling, Huntington said he has continued to explore the market for upgrades. The most likely path to improvement, however, is through players coming off the injured list and prospects like Keller stepping up.

“We’ve had to force-feed some guys into roles that maybe they’re not ready for. That’s on me, and it’s on us that we didn’t have enough depth or we didn’t properly evaluate our depth,” Huntington said. “It’d be nice to get some guys healthy; that would help. Get Williams back, bring up a young prospect like Keller when he’s ready or closer to when he’s ready, get a Chris Stratton back. Now, you start to move guys back into roles where they’re more comfortable. Get [Keone] Kela healthy at some point here down the road.

“We continue to look externally to see if there are some available options. The asks are really high right now on very marginal upgrades, and/or there are very few marginal upgrades available.”

Huntington touched on a few other topics in a chat with reporters.

On Kingham’s future: “History tells us that a guy with some [prospect] pedigree, these guys tend to get traded. We feel like we’ll be able to get something in return for him. If not, then we’ll have to go through the outright waiver process. We may lose him. We knew that going in to the decision. Just felt like an out-of-options guy that’s struggled hamstrings your club a little bit. For whatever reason, we weren’t able to help Nick become the player he wants to be and we thought he could be.

“If he is able to clear waivers, we’re going to go back to work to get him to become the best Nick Kingham he can be. If he doesn’t, we’ll get the best we can get in return and wish him well.”

On whether they’ll make any of their five outfielders available in a trade: “We like all five. But we’re always open to opportunities to make this club better. If something makes sense, then we’ll certainly explore it.”

On sending rookie shortstop Cole Tucker to Triple-A: “He played really good defense but [just] survived offensively. And when you have holes [in your swing], Major Leaguers find them quickly. We joked with Cole, 'You know, they found your holes in five games.' And he joked back, 'It was five at-bats.' So he's going down to refine his approach and, when he comes back, he'll be better for it.

“Sitting with Cole [on Saturday] was really hard, to send him out, because you love the young man and what he's going to do. But it just felt like it was the absolute right move right now, to get him to go play regularly and close up those holes."

On their progress signing Draft picks: “Nothing to say officially at this point in time, but remaining optimistic that we’re going to be close [to getting] a large number of that group done -- and hopefully done quickly.”