RHP Devin Williams
There's a very high chance that Brewers fans have seen Devin Williams pitch in a Brewers uniform for the last time, and it was when he blew the save in Game 3 of the NL Wild Card. It would be an unfortunate end to a very dominant run in Milwaukee for Williams.
Williams is entering his final season of team control. Right before heading to an arbitration hearing last year, the Brewers and Williams agreed to a $7MM salary for 2024 with a club option for $10.5MM for 2025. The Brewers can pick up that option, and likely will, and avoid having to negotiate an arbitration salary again. If they decline the option, they'll have to go one more round of arbitration. That is, unless they trade Williams first.
The Brewers don't like paying big salaries for relief pitchers, which is why the Josh Hader trade ended up happening. They're on the same path with Williams except this time they learned their lesson to make that move in the offseason. Trading Williams at mid-season, when they're likely back in a pennant race and he's a simple rental won't net Milwaukee much of a return, meaning this winter is their last best chance to cash in on Williams' value before he hits free agency.
Milwaukee has plenty of options to take over the closer's role next year. Williams can net the Brewers an immediate everyday player to plug whatever hole they need, plus perhaps some prospects. There's little chance Williams signs a long-term deal with the Brewers. Their philosophy on relievers hasn't exactly changed much over the last several years. If they wouldn't pay Hader, they won't pay Williams.
For what it's worth, the Game 3 implosion Williams had doesn't have any bearing on the Brewers trading him. A Williams trade this winter appeared highly likely even before that game. The playoffs changed nothing about this, except the last memory fans will have of Williams as a Brewer.
One year of a high priced reliever that won't re-sign and would fetch a huge return is a surefire trade candidate. Milwaukee has done it before and they'll likely do it again.