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I think Ortiz has been for the most part pretty outstanding defensively, and I believe the odds pretty strongly favor them rolling with both him & Durbin on the left side as opposed to competing with other teams for whatever else is out there & overpaying.
There was a plan here, and it did not include Boeve & Wilkin being derailed by injuries (there's at least a chance they'd both be in AAA by now & ready to help) and Black being plagued both by health issues and, frankly, by not being all that good when he was here last year. Someone mentioned Contreras possibly playing some 1B. That's questionable but even then, Quero would be the replacement at C and, once more, we're talking about a guy who missed a full year of development by getting hurt.
There's a path to success--great success--for a team in Milwaukees' position. But that doesn't include people getting hurt, screwing up the timeline & then simply overcoming that by using prospect capital to buy replacement parts. And as others have mentioned, Durbin & Ortiz HAVE been better at the plate recently.