The main subplots of this 2017 season have been pretty obvious; the Dodgers are unstoppable, Aaron Judge is a power-hitting monster, and Clayton Kershaw, Max Scherzer, Chris Sale and Corey Kluber are really good at what they do.

Flying a bit under the radar, however, are some shortstops previously best known for their glovework (or not known at all) who have begun to hit. Is the offensive production being generated by the likes of Elvis Andrus, Andrelton Simmons and Johan Camargo for real? Let’s use batted-ball data to answer some questions.

Andrus, now 28, has been the Rangers’ everyday shortstop since he was 20. Until last season, he had never posted a wRC+ of 100 or a single-season SLG of .400 or higher. Going back over the entirety of his professional career, his single-season home run total had never broken double digits. This year, he’s flirting with a .500 SLG, and would seem to be a lock to reach 40 doubles and 20 homers. Prior to 2017, his calling cards were his defense and his durability; he’s played 145 games or more in every season of his career.

Simmons, 27, was the Braves’ second round pick in 2010. He raced to the big leagues in just over two years thanks to his defensive wizardry. After a .289-.335-.416 line in his 49-game rookie trial, he has been a thoroughly mediocre offensive player, posting seasonal wRC+ marks of 91, 71, 81 and 91 for the Braves and Angels, with a career high full-season SLG of .396 in 2013. He’s hitting over .300, with a SLG over .450 at present, and helped keep the Angels afloat during Mike Trout’s recent absence.

Camargo, 23, might be the most surprising story of all. Each year, I compile a list of minor league position player prospects comprised of players who meet various production/age-based milestones. No position adjustments are made; it’s all about generating a master follow list, triggering more traditional methods of evaluation on the group. About 300 full-season league position players qualify each season. Camargo didn’t qualify from 2014-16 (though his short stint at the beginning of 2017 should earn him a slot). He hit all of 14 homers in over 2000 minor league plate appearances. Suddenly, it’s Camargo, not Dansby Swanson, manning the shortstop position in Atlanta.

How real are these players’ newly raised levels of offensive performance? Let’s drill down into their plate-appearance-frequency and batted-ball-quality data to get a better feel.

In the two tables below, such data is provided for all three players.

Plate Appearance Frequency Data Name POP % FLY% LD% GB% K% BB% Andrus 2.8% 30.1% 19.6% 47.5% 16.7% 5.1% A.Simmons 3.0% 26.3% 19.6% 51.1% 10.4% 7.5% Camargo 4.9% 25.9% 21.7% 47.6% 21.8% 5.1%

Contact Quality/Overall Performance Data Name UNADJ C U-FLY-A U-LD-A U-GB-A ADJ C wRC+ PRJ PRD Andrus 116 89-63 143-97 133-88 80 114 82 A.Simmons 94 71-46 93-96 142-103 78 122 98 Camargo 120 89-74 160-101 108-108 90 101 80

The first table lists each player’s K and BB rates, as well as the breakdown of all of their BIP by category type. For this table, color-coding is used to note significant divergence from league average. Red cells indicate values that are over two full standard deviations higher than league average. Orange cells are over one STD above, yellow cells over one-half-STD above, blue cells over one-half STD below, and black cells over one STD below league average. Ran out of colors at that point. Variation of over two full STD below league average will be addressed as necessary in the text below.

The second table includes each player’s Unadjusted Contact Score. This represents, on a scale where 100 equals league average, the actual production level recorded by each player on balls in play. Basically, it’s their actual performance with the Ks and BBs removed. Their Unadjusted and Adjusted Contact Scores for each BIP category are then listed. Adjusted Contact Score represents the production level that each player “should have” recorded if every batted ball resulted in league-average production for its exit-speed/launch-angle “bucket.” Players assessed an extreme grounder-pulling penalty are in red font.

Finally, overall Adjusted Contact Score, actual wRC+ and Projected Production are listed. Projected Production adds back the Ks and BBs to the Adjusted Contact Score data to give a better measure of each player’s true performance level.

Andrus, though not a particularly productive offensive player for most of his career, has always brought some positives to the table. His strikeout rate has always been materially lower than league average, and his liner rate has tended to be league average or better. This gave him a reasonably high floor, but his utter lack of thump and extreme ground ball tendency provided little ceiling.

In 2017, he has traded out some of his strengths, at least to a small extent, to get boosts elsewhere. His 2017 fly ball rate to date is by far a career high; in exchange, his K and pop up rates are up, but are still at very reasonable levels. His liner rate isn’t a high as usual, but it still hovering in the lower end of the average range.

His Contact Quality profile is a bit complicated. His Unadjusted Fly Ball, Liner and Grounder Contact Scores are all materially higher than his adjusted marks. Normally, that is a clear sign of very good fortune. While there is some of that at work, particularly on the line drives, there are other factors to consider as well.

First, and most obviously, Andrus can fly. One would expect him to outperform his authority-based projections on grounders to a measurable extent, and on liners by a lesser margin. What he has learned to do on fly balls, however, is a bigger deal. This is what has given us Brian Dozier and Ian Kinsler, two players who outperformed BIP-based data during their respective peaks.

It’s all about selective pulling in the air. The vast majority of Andrus’ power has been of the dead pull variety. Recognize the pitch you can hammer, and hammer it. Sounds simple, but so many talented players never master it. Andrus has come a long way in a short time in this department.

This isn’t to say that he hasn’t added physical strength. This is no longer the 20-year-old string bean that he once was. His average fly ball authority is up from 86.1 mph in 2016 to 89.4 in 2017, and his average liner authority has climbed from 90.2 to 93.2 mph over the same time frame. His Adjusted Fly Ball and Liner Contact Scores have jumped modestly from 46 to 63 and 87 to 97 from 2016 to 2017.

I have always thought Andrus might have a year like this in him, but I don’t see it as a gateway to even greater things. The speed will dissipate, and may have already begun to do so, and there is a nice chunk of luck in his 2017 numbers. There is absolutely no reason, however, that he can’t churn out some more 15+ homer seasons while playing a solid defensive shortstop.

Simmons has always brought one clear positive to the table offensively — he never strikes out. He typically has struck out over two full standard deviations less than the average MLB regular. Like Andrus, he has countered the high floor afforded by such a high contact rate with tons and tons of weak contact, most of it on the ground.

This year, he’s traded on some of his strengths in a similar manner to his Rangers’ counterpart. His K rate has crept up, and while an increased fly ball rate isn’t a bad thing, it did drag his pop up rate along with it. Also, like Andrus, he is outperforming his contact-based projections on fly balls (71 Unadjusted vs. 46 Adjusted Contact Score) and grounders (142 vs. 103). Unlike Andrus, you can’t credit the grounder production to any sort of speed premium; it’s basically simple good fortune.

The main reasons for his power increase fall right line with the Andrus recipe; more fly balls, hit a bit harder, with selective pulling boosting his home run total. His average fly ball authority has risen from 86.0 mph in 2016 to 87.5 mph in 2017, while his average liner velocity has increased from 90.5 to 92.2 mph. No great shakes still, but his Adjusted Fly Ball and Liner Contact scores rose from 26 and 91 in 2016 to 46 and 96 in 2017. Every little bit of improvement counts, especially when you’re adept at hooking hittable pitches down the line.

Adjusted for context, Simmons has been about a league average offensive player this season. League average offense with historically great defense at a premium position works for me. And if this selective pulling in the air business sticks, he could be even a little better with the bat, though I’ll mark down 2017 as his offensive crest.

Lastly, we have Camargo, a switch-hitter. There is one scary red flag in his frequency profile. A fairly extreme grounder hitter like Andrus and Simmons, Camargo’s pop up rate as a percentage of his fly ball rate is scary high. Go find me the productive major league hitters who hit a bunch of grounders AND a bunch of pop ups. I’ll wait.

There are a couple more red (or at least orange) flags on his contact quality profile. He has been extremely lucky on liners this year, batting .794 AVG-1.176 SLG (160 Unadjusted Contact Score) despite almost exactly league average authority (101 adjusted). He also received a (small) extreme grounder-pulling penalty. He has already established himself as a clear infield overshift candidate, which offers a ton of batting average risk moving forward, It’s mitigated a bit by his switch-hitter status, but is still a concern.

Then there’s the small matter of his ugly walk rate. There is no real safety net — like Andrus and Simmons’ low K rates and Andrus’ speed — to protect him when things turn down. Of course, at 23, and with a strong glove and no real expectations, he has time to figure it out. Perhaps he can trade on his BIP authority — better than Andrus/Simmons on each BIP type — for more contact or more walks in time.

The underrated difference among these three somewhat similar offensive players is the two established players’ nuanced ability to keep defenders honest, especially in the infield, with their ability to use the field, coupled with their emerging selective pulling in the air. It’s a skill set that can transform them from strong defenders who aren’t automatic outs into mega-stars.

I throw a ton of numbers at you in this space, but when you get down to it, it’s about a whole lot more than numbers. Elite defenders at premium positions are some of the most intriguing players in the game. They combine athleticism, creativity and discipline — three traits that don’t often exist in one package — as few others can. Elite defensive catchers and center fielders have athleticism and discipline, but creativity is clearly the shortstop’s purview.

The game’s history is filled with creative, disciplined shortstops who entered the game as automatic outs, or close to it. Ozzie Smith springs immediately to mind. They can visualize doing almost anything on a baseball field from a very young age; and they tend to arrive at the major league level at that young age because of their defense, far before they physical ship, and their offense, comes in.

Andrus and Simmons are following in Ozzie’s footsteps, with less OBP and more power. Camargo isn’t a strong bet to follow their path, though he has at least marked himself as a controllable asset and a far better piece than the Braves thought they had.