While last season was an injury-shortened wreck for the Mariners’ Mitch Haniger, you can’t dispute that he’s a highly valuable outfielder when he’s able to take the field. Haniger came into his own during his first extensive action in 2017, and he was a deserving All-Star during the next season, in which he hit .285/.366/.493 (137 wRC+) with 26 home runs and 4.5 fWAR. With three years of control left, Haniger could either continue to serve as a key Mariner or re-emerge as a desirable trade chip, leaving the M’s in a good spot in both cases.
As for how Haniger became a Mariner, we can start by revisiting the 2011-12 offseason. Prolific slugger Prince Fielder, a Brewer from 2005-11, reached the open market after the last of those seasons. He was a Type A free agent, which is a concept that’s now extinct in the majors, but losing Fielder entitled the Brewers to a compensatory pick in the 2012 draft. They did indeed see Fielder depart, as he went to the Tigers on a nine-year, $214MM contract. That left the Brewers with the 38th overall pick, which they used on Haniger.
While Haniger was a decent minor league hitter at the lower levels in the Milwaukee organization, he never played in the majors with the Brewers. They instead traded Haniger and left-hander Anthony Banda (now a Ray) to the Diamondbacks at the July 2014 deadline for outfielder Gerardo Parra. The Brewers didn’t make the playoffs that year or the next one – Parra was on their roster both seasons – and they traded him to the Orioles for righty Zach Davies at the 2015 deadline. Davies was effective as a Brewer from 2015-19, though they dealt him to the Padres in a four-player swap that delivered infielder Luis Urias and lefty Eric Lauer to Milwaukee over the offseason.
So, in the wake of the Parra trade, how did Haniger end up in Seattle? Let’s go back to November 2016, when the D-backs sent him, infielder Jean Segura and righty Zac Curtis to the Mariners in a blockbuster trade for infielder/outfielder Ketel Marte and righty Taijuan Walker. Segura’s now a member of the Phillies, who acquired him from the M’s in a December 2018 that brought shortstop J.P. Crawford and some guy named Carlos Santana to Seattle (though Santana never played for the club). Marte has turned into a superstar in Arizona, meanwhile, Walker’s now back in Seattle after a couple injury-ruined years in the desert, and Curtis is out of baseball.
This goes to show how much one team’s decision – in this case, the Brewers letting Fielder go in free agency – can affect the league. Had the Brewers simply re-signed Fielder, which was out of the question for the low-budget team, you never know what would have happened to any of the aforementioned clubs or players. Milwaukee’s inability to keep Fielder did lead Haniger to Seattle, which is no doubt pleased to have him in the fold for at least the next few seasons, but it did lose Marte when it acquired him.