The Windup Newsletter ⚾ | This is The Athletic’s MLB newsletter. Sign up here to receive The Windup directly in your inbox.The Mariners’ piggyback is back, but now it’s a rotational piggyback rotation, with more piggies on a bunch of different backs. Wait, no … it has to be your bull.Lemme start over: I’m Levi Weaver — welcome to The Windup!Plot Twist: Mariners’ piggyback plan evolvesWe told you a couple of weeks ago about the Mariners putting Luis Castillo and Bryce Miller into a piggyback situation (when one starter starts the game and the other starter finishes it), and that the pitchers didn’t seem particularly pleased about it, despite the uptick in results.Well, there has been a development.First, the Mariners went to a six-man rotation, but that didn’t quite work, for the same reason it always doesn’t quite work: the extra starting pitcher means you have one fewer relief pitcher at any given time. The Mariners went 4-6 on a road trip to Detroit, Baltimore and D.C., and while the rest of the AL West did very little to make that a problem, the team seems to have decided there’s a better, more creative option.How about a rotating piggyback … rotation? I’ll let John Trupin of Yahoo! Sports explain:“Instead of limiting the piggyback to Luis Castillo and Bryce Miller, after apparent discussion and planning with the entire rotation, the club will be rotating the piggybacking through all six starters to afford each an opportunity to be stacked with another starter at some point. Reportedly, the decision (or at least the input from the rotation) was unanimously in favor of sharing the start-sharing load.”Wait, so all the starters came together, saw that two of their brethren were being made to piggyback and collectively said, “OK, we’ll all piggyback a little to share the load”?From the outside looking in, that sounds like suspiciously incredible clubhouse vibes. At the very least, the reception seems much more positive than it did when we checked in on this story last month.Middle Relief: Yordan Alvarez in Milwaukee?Chad Jennings weighed in on a few readers’ trade proposals this week in our MLB Mailbag. Here’s one I thought did a good job of thinking outside the box without turning the submission into an avant-garde bit of mailbag performance art.