Lorenzo Cain is a star in the outfield, and it's hard to imagine that would be any kind of a controversial statement. By Outs Above Average, the Statcast™ range-based metric, he's at +16, which puts him in the top 5 this year, just like he was in 2017.
While Cain is having a good year at the plate in his first year with the Brewers, hitting .311/.401/.427 with 10 homers and 28 steals, it's his defense that's putting him in the National League Most Valuable Player Award conversation. While he's never won a Gold Glove Award, that doesn't really matter. He's a stud.
Cain is also one of the best outfielders at going back to make the catch behind him, and he knows it. We know that too, because we asked him.
"I think it would show [I am] better going back than coming in," Cain said recently. "I've always felt comfortable going back. It's a skill you work on, but some of it has to be God-given, you know what I mean? There's some natural ability. But I definitely put in a lot of work going back on balls. For me, those are tough ones, catching balls over your head. I've never been afraid of the wall."
"I would definitely be interested in checking out the numbers," he continued.
Now Cain can, and so you can you. He's exactly right. Since the start of 2016, Cain has been worth +44 Outs Above Average, fourth best behind Ender Inciarte, Billy Hamilton and Mookie Betts. That breaks down into +28 outs going back and +16 coming in. The +16 coming in is still very good -- it is expressed as outs above average, after all -- but the numbers back up exactly what Cain is saying. He's more productive going back.

You can see that now for Cain or for any other outfielder, dating back to 2016, on the new "Directional Outs Above Average" leaderboard available on Baseball Savant.
In addition to expressing a player's seasonal OAA total, like how Harrison Bader and Inciarte are tied for the 2018 lead at +20 OAA, the new leaderboard will split up a player's performance into six 60-degree directional slices, where "in" is always "towards the plate." It also sums the three "in" columns and the three "back" columns into aggregated numbers. So while you might note that this year Cain is better going back (+12) than he is coming in (+4), Bader is far better coming in (+14) than he is going back (+6).
For someone like Delino DeShields of the Rangers, his 2018 looks like this:

The takeaway from that ought to be, "Wow, DeShields is fantastic going back, but he hasn't done as well coming in." That's exactly right, because he noted the same thing.
"Each year is different," said the Texas outfielder before a recent game against Oakland. "Last year, I was working on coming in on balls. This year, more so going back over my shoulder, reading how far I am from the wall, seeing where the ball is in relation to the wall. It's definitely something I have been working on on a daily basis from Spring Training."
So DeShields put some effort into improving going back this year, and it showed. In 2017, he was +5 going back, which is solid. This year, DeShields is +13, which is spectacular, second best of any outfielder. But last year, he was only average coming in, at +0 OAA. This year, DeShields is about right there again. He's noticed that, too.
"This year, I don't think I am as good as last year [at coming in on balls]," he said. "Maybe because I have been working a lot on going back on balls, taking away from me coming in. It's a progression for me. I know I can come in on balls, I know I can go back on balls now. It's now finding that place where I am comfortable doing both, being exceptional and really good at it."

Because we can look at each outfielder for each year, we can find some interesting outcomes. Some outfielders have shown a particular skill at coming in, like Albert Almora Jr., who is +10 coming in but only +1 going back. Teoscar Hernandez has been a net negative this year (-6 OAA), but that's because he's been very poor going back (-7) and slightly above average coming in.
Meanwhile, there's Colorado's Carlos Gonzalez, who has been fantastic coming in (+6 this year, +16 since 2016) while being weak going back (-4 this year, -11 since 2016). That's the third-largest gap since 2016 behind Adam Duvall (33 outs better going in than back) and Gregory Polanco (27 outs better going in).
Every year, Gonzalez is good coming in: +2 in 2016, +3 in '17 and +6 this year. Every year, he's worse going back: -3 in '16, -5 in '17 and -4 this year.

Earlier this year, Gonzalez noted how he uses scouting reports to inform his defensive approach.
"It's important to get a really good first step, but the other thing that helps you a lot is knowing what the count is and knowing who's at the plate," Gonzalez said. "The reports give you so much information about where the guy's going to hit the ball. It happens to me a lot [at the plate] -- they know where I'm gonna hit it, and they're normally playing up the middle with the shift. There's a lot of information over the years that makes you a good defender."

Others are great all around, like Inciarte, who is the best of anyone coming in since 2016 (at +35), but also the third best going back (+29). Some are just consistent, like Michael Trout, who is average or above in all six directions this year without being more than +2 in any single one.
Then there's Adam Engel of the White Sox, an outfielder so skilled that he robbed three home runs in the span of three days last month. No, really.

Your eyes didn't deceive you. Engel is tied with Hamilton for third among outfielders this year with +17 OAA. Last year, he finished third behind Byron Buxton and Inciarte with +20 OAA. Despite the fact that Engel only made his Major League debut late last May, he's already second to only Hamilton since 2016 in outs above average made going straight back, at +31.
Cain gets the last word here, however. 
"I feel like the numbers game is tailored more towards guys that have similar games to mine," he said. "The stuff they've come out with like WAR and baserunning numbers and defensive numbers, they're tailored to my game. I'm not a guy who can go out there and hit you 30 homers or whatever, drive in 100. I'm not going to do that. But the new stuff is tailored to guys with my skill set. I think a lot of teams are looking for that kind of player with that overall game. I've got a little bit of everything."
Cain is right. Every time an advanced look at baseball emerges, he tends to look good in some way. This time, it's that he's a star going back to make the big catch. Cain already knew that, of course. Now you do, too.