Mike Trout needs no introduction, so I won't waste anyone's time with one. He's historically great, in the literal sense of the word, and the Angels are lucky to have him. He's been dominant since his first full season in 2012 and is currently signed through 2020, meaning the halfway mark of his time with Anaheim (barring another extension or re-signing) is imminent.
To reiterate what absolutely doesn't need reiterating: Trout has been stupid good thus far, putting up the tenth-best four-year peak since 1920 in his only four years of playing. The Angels, however, have... fallen short of expectations over that time period. From 2012–2015, they've made the playoffs once, winning the AL West in 2014 before being swept by the Royals, and averaged about 88 wins. That struck me as low, given that Trout has averaged 9.5 WAR over that period, per FanGraphs. When you're spotted a player worth essentially two all-stars, it shouldn't be that hard to succeed, right?
That's what I aimed to find out with this article. Using the FanGraphs WAR leaderboards, I looked at all player-seasons since 1920, a somewhat arbitrary endpoint that was chosen basically to include Babe Ruth. I then calculated the WAR generated by each player in the last four years for his team. This is similar to, but not quite, rolling four-year WAR; if Trout had been traded to the Twins in 2014, for example, he would've had a 17.0 figure for the Twins after 2015 and a 20.8 figure for the Angels after 2013.
The sample is the top 100 four-year periods by this measure, on which Trout ranks 28th (down from the above FanGraphs article because of individual players showing up multiple times on this list). The best four-year span is Babe Ruth's 1920–23; the worst to make the sample is Chase Utley's 2006–09, over which period he averaged just under 8 WAR annually.
For each team-year with a player on the list, I looked at their success in the previous four years, including win percentage and World Series appearances or victories for all years, LCS appearances for 1969 on, LDS appearances for 1993 on, and Wild Card appearances for 2012 on. How did the teams with these historically-excellent players do?
The unsurprising answer is "pretty friggin' great." Turns out getting an average of almost 9 WAR each season from a single player is good for a team. Who knew?? They averaged a winning percentage of .570, good for 92 wins in a 162-game season. In other words, in the regular season, teams with these superstars were as successful as the 2015 Dodgers, on average. Mike Trout's Angels, as mentioned above, averaged a winning percentage of .539, or 88 wins, the 30th-lowest rate of the 100. Not the worst (that dubious honor goes to Ernie Banks' Cubs of 1957–1960, who won only 43 percent of the time despite his 31.5 WAR), but solidly below-average for the sample.
What about the more visceral results? No one is talking about the Royals' or Mets' win percentages from this past season; how did these teams do in the postseason? Also unsurprisingly, clubs that win a lot tend to reach the postseason frequently and then win a lot there as well. The teams in the sample averaged .7 World Series wins in the four-year period and reached the World Series (but lost) an additional .5 times. That's really good! The Angels with Trout: 0 of either.
Since the Divisional Series debuted in 1995, teams in these windows have at least reached it an average of 1.8 times. But this result is a little bit skewed, since the only other team-years to have only one LDS appearance are the Cardinals with Albert Pujols, from 2007–10, and the Giants with Barry Bonds, in each of 1993–96, 1994–97, and 1995–98. The repeated appearances of those Giants really pull the average down.
So it's pretty clear that the Angels have failed to capitalize on an historic stretch from Mike Trout in the way most other teams with similarly great players have. But it's not all doom-and-gloom, Angels fans! Mike Trout is still really good and is almost certainly going to continue to be really good. For his 2013–16 seasons not to make an updated version of this list at the end of next season, he'd have to put up less than 3.8 WAR, which seems... unlikely. If this analysis shows anything, it's that teams with really fantastic players have tended to do very well. The Angels haven't, but they still have their really fantastic player and will until 2020! That's so many seasons away!
To go back to Bonds and the mid-90s Giants, they provide an obvious and optimistic precedent. In 1995 and 1996, the Giants weren't just not-good-enough (as the Angels have been recently), they were downright terrible. But in 1997, they got a new General Manager, and a revamping of the team to be more than just Bonds + mediocrity led to a highly successful run from 2000 to 2003, behind Bonds and very good supporting cast members like Rich Aurilia and Jeff Kent.
It's easy to see parallels to the Angels' current situation, who have spent the last few years without much in the way of depth behind Trout. It's not crazy that they haven't had much success despite Trout's dominance, even if it is somewhat surprising. What this shows is that there's a clear and relatively easy path forward, if the Angels' new leadership can find it.
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Henry Druschel is a Contributor at Beyond the Box Score. You can follow him on Twitter at @henrydruschel.