Houston Has No Problems With Michael Brantley

Is it premature to call Michael Brantley the best free agent signing of the 2018-19 offseason? Probably, but that depends on how one defines “best.” Also important are the words “so far,” which are admittedly not in the initial question, but are still significant nonetheless. If we are trying to determine a total return on investment, we’d need to evaluate the impact of many factors, including those not specifically seen on the field.

By this process, one could argue that Bryce Harper has been the “best” free agent so far, generating increased interest in baseball in Philadelphia (attendance numbers are an indication of this) and setting the professional sports record for most jersey sales in the first 24 hours of a launch. Those are certainly positive numbers for the Phillies’ brass, but that’s not what I’m looking at here.

Narrowing our focus down to on-field production alone, no 2018-19 free agent signee has been better so far than the Astros’ new outfielder. Though 37 games, Brantley has produced 1.7 WAR, putting himself in first by a 0.4-win gap over the next closest player, Charlie Morton. He’s half a win ahead of the next position player, with Eduardo Escobar and DJ LeMahieu each having been worth 1.2 wins.

(Ryu, Escobar, and Moustakas were all re-signings, but they were part of the 2018-19 free agent class for the purposes of our free agent tracker.)

In fact, Brantley is enjoying one of the best starts to his career. He’s currently 11th in baseball in WAR and 11th in wRC+. His .340/.390/.603 (168 wRC+) slash line is — for a lack of a better word — absurd, and this level of offensive production in any 36-game stretch hasn’t been matched since the middle of 2015, when he went on an August tear (.406/.463/.604, 189 wRC+).

Brantley almost certainly won’t sustain this pace over the course of a whole season — his 23.1% HR/FB rate will come down, and his .336 BABIP probably will, too. Both ZiPS and Steamer see significant regression over the course of the rest of the season, but they still see him as a well-above-average hitter the rest of the way. ZiPS has him at a 125 wRC+ and 2.3 WAR in 432 plate appearances, while Steamer has him at a 123 wRC+ and 1.9 WAR in 389 plate appearances. That would peg Brantley for somewhere between 3.6 and 4.0 WAR in 2019.

There’s no doubt about it: Brantley is having a really nice season. But how does his early going in Houston compare to free agent outfielders from previous years?

I compiled a list of every free agent outfielder since the 2011-12 offseason, giving me seven years worth of data to evaluate. Then I sorted each contract by its annual average value and looked for multi-year deals with AAVs within $5 million of Brantley’s $16 million per year guarantee. In order to figure out which free agents made the most immediate impact, I only looked at the WAR they produced in the first year of the new deal. Because of this, outfielders who signed contracts during the 2018-19 offseason are omitted; they haven’t completed a full season. Here’s the full list, 13 outfielders deep.

When looking at this chart, I’m drawn to the top name: Cain. He made quite the impression on the Brewers in his first year of his new contract last season, slashing .308/.395/.417 (124 wRC+) over 620 plate appearances while also posting outstanding outfield defense. The acquisition of Cain (and, as we all know, Christian Yelich) helped to turn the Brewers from an 86-win team in 2017 to a division-winning 96-win team in 2018. Talk about a free agent signing making an immediate impact.

A similar story can be told for the second name on this list: Victorino. He’s not solely responsible for Boston’s incredible single-season turnaround from 2012 to 2013 — when they went from finishing last in the AL East to winning the World Series — but his 4.7 WAR that year certainly contributed in a big way. That all goes without mentioning Victorino’s most famous moment in a Red Sox uniform, a go-ahead grand slam in the bottom of the seventh inning in Game 6 of the ALCS.

For Brantley, a similar regular season impact probably won’t be possible, purely due to circumstances outside his control. Unlike both Cain and Victorino, who joined teams that did not make the postseason the year prior, Brantley is just further icing on the cake for the Astros. This is a team that went 103-59 last season, setting the franchise’s single-season wins record, and won the World Series a year prior. The Astros signed Brantley not to get over the hump and into the playoffs, but with the intention of winning another World Series.

Still, Brantley is projected to make one of the best first-year impressions of any free agent outfielder over the past seven seasons, and he probably has a half-decent shot of surpassing Cain’s 5.7 WAR total to rank atop this list — after all, these point estimates are based on the 50th percentile projection alone.

Regardless, one thing is for certain. Brantley has come out out of the gate on fire for the Astros, helping them build their current four-game lead in the American League West. Houston might not have needed Brantley in order to help them get to the playoffs, but they certainly have no problem with him helping to lead the charge.