As the 2017 season begins, so does the third season of Statcast™, the state-of-the-art technology that has tracked every play in every Major League ballpark since Opening Day 2015. And with two full seasons of data now collected, plus advances in applying that data, Statcast™ is better than ever. New metrics, such as Catch Probability and Hit Probability, will provide a deeper layer of analysis and further our understanding of the game.
With that in mind, here are five Statcast™ storylines to know about the Phillies heading into the 2017 season.
1. Play the hook
The curveball was an important pitch for Jeremy Hellickson in 2016, as opponents whiffed on more than 30 percent of their swings against it while batting .159 with a .262 slugging percentage. Hellickson's average spin rate on the pitch jumped from 2,781 rpm in 2015 -- already one of the highest marks in MLB -- to 2,970 rpm. Out of 117 pitchers who had at least 200 curves or knuckle-curves tracked last year, that was the highest.
Highest average curveball/knuckle-curve spin rate in 2016 (minimum 200 thrown)
1. Jeremy Hellickson: 2,970 rpm
2. Tyler Skaggs: 2,905 rpm
3. Lance McCullers: 2,901 rpm
4. Trevor Cahill: 2,898 rpm
5. Kyle Hendricks: 2,883 rpm
2. Whiffs aplenty
In just his second start with the Phillies last April 14, right-hander Vince Velasquez flashed his potential with a 16-strikeout shutout against the Padres. Velasquez racked up 27 total swings and misses in the game, including 20 on his four-seam fastball, which was the most by any pitcher in 2016. Over the course of the season, Velasquez got whiffs on 27.4 percent of swings against his four-seamer, the highest rate among 46 pitchers who faced at least 500 such swings.
Highest missed-swing rate on 4-seam fastballs in 2016 (minimum 500 swings)
1. Vince Velasquez: 27.4 percent 
2. Justin Verlander: 27.1 percent
3. Jake Odorizzi: 25.0 percent
4. Jacob deGrom: 24.7 percent
5. Max Scherzer: 24.0 percent

3. Strong arms
One of the strongest arms behind the plate last season belonged to the Phillies' Cameron Rupp, who on stolen-base attempts averaged 86.5 mph with his "max-effort" throws -- those harder than his 90th percentile. That ranked third among catchers with at least 20 throws on steal attempts. Meanwhile, prospect Jorge Alfaro reached 89.4 mph on his only tracked competitive throw of 2016, which came on a wild pitch. Then, while competing for Colombia in the World Baseball Classic this spring, Alfaro unleashed throws of 84.6 and 85.5 mph on steal attempts. Only six catchers in '16 (Rupp included) managed a harder throw than the latter on a caught-stealing.
Highest average max-effort arm strength on SB attempts in 2016 (minimum 20 total throws)

1. J.T. Realmuto: 87.0 mph
   
2. Martin Maldonado: 86.8 mph
   
3. Cameron Rupp: 86.5 mph
   
4. Yasmani Grandal: 84.7 mph
   
5. Anthony Recker: 84.6 mph

4. Ground game
Acquired by the Phillies last November, veteran Howie Kendrick has enjoyed a solid big league career, with a .289 batting average and 106 OPS+. But his grounder-heavy ways also might be a hindrance at times. Kendrick, whose line fell to .255/.326/.366 for the Dodgers last season, has the third-lowest average launch angle of the Statcast™ Era (2015-16) at 3.1 degrees. Over that time, he has posted a .303 average on batted balls with a launch angle below 10 degrees -- but only a .328 slugging percentage. On balls of 10 degrees and higher, he has hit .447 and slugged .798.
Lowest average launch angle in the Statcast™ Era (minimum 500 batted balls)

1. Christian Yelich: 1.7 degrees
   
2. Yunel Escobar: 2.8 degrees
   
3. Howie Kendrick: 3.1 degrees
   
4. Dee Gordon: 3.4 degrees
   
5. Andrelton Simmons: 3.7 degrees

5. Get down the line
No player in MLB last season racked up more infield hits than switch-hitter Cesar Hernandez, whose 36 edged out teammate Odubel Herrera's 33. But while Hernandez's total included 15 bunts, Herrera's included just four. So when it came to "max-effort" home-to-first times on non-bunts from the left side, the two were virtually tied at 3.98 seconds -- both inside the Top 10. (Max effort includes only times faster than a player's 90th percentile, and bunts are set aside because they give players a head start.)
Fastest average max-effort, non-bunt home-to-first times for LHB in 2016 (minimum 100 total tracked times)

1. Billy Burns: 3.82 seconds
   
2. Dee Gordon: 3.86 seconds
   
3. Billy Hamilton: 3.88 seconds
   
4. Kevin Kiermaier: 3.94 seconds
   
5. Ichiro Suzuki: 3.94 seconds
   
6. Norichika Aoki: 3.95 seconds
   
7. Odubel Herrera: 3.98 seconds
   
8. Cesar Hernandez: 3.98 seconds
   
9. Brett Gardner: 3.99 seconds
   
10. J.B. Shuck: 3.99 seconds