Categories: Analysis

How Jake Arrieta and Nick Pivetta can be productive in 2020

After the Philadelphia Phillies signed Zack Wheeler in December, many fans expected the team to continue adding to a rotation that badly underperformed in 2019. The Phillies had other plans, however, opting to stay under the luxury tax threshold and using most of their remaining budget on shortstop Didi Gregorius.

Nick Pivetta and Jake Arrieta struggled for much of 2019, but there is a path to success for both pitchers in 2020. (Left: Rich von Biberstein/Icon Sportswire; Right: Nick Tre. Smith/Icon Sportswire)

This means the three spots in the rotation behind Aaron Nola and Zack Wheeler will be filled by some combination of Jake Arrieta, Zach Eflin, Vince Velasquez and Nick Pivetta, with the odd man out most likely destined for the bullpen. Each of these pitchers was in and out of the rotation last season because of injuries or poor performance, but for the Phillies to mount a serious playoff push in 2020, the back half of the rotation must be better.

With Bryan Price replacing Chris Young as pitching coach, the team is banking on a return to at least 2018 standards from a few of these pitchers. Fortunately, there is hope that they can fix what ailed them last year and be productive this season.

Jake Arrieta

In 2020, the Phillies nominal No. 3 starter behind Aaron Nola and Zack Wheeler will be Jake Arrieta. He’s the only one of the “other” starters already guaranteed a place in the rotation. While his best days are clearly behind him, the team will be hoping that Arrieta can put together a better showing in the last year of his contract than he has in the first two seasons. This is largely dependent on the soon-to-be 34-year-old’s durability.

Troubled by a knee injury in 2018, Arrieta again suffered health problems in 2019, pitching most of the season with bone spurs in his throwing arm before his season came to an end when he was placed on the injured list in August after only 24 starts. Presumably back at full strength after a procedure to remove the bone spurs, there is some hope that the former National League Cy Young Award winner can provide much-needed stability to the back end of the rotation.

To do this, Arrieta will have to get more out of his slider than he did last year. Once his favored putaway pitch while at his peak, the pitch was lit up by opposing batters last year before Arrieta stopped using it entirely in his last four starts, likely because of pain caused by the bone spurs.

His usage of the slider has declined from nearly 29% in his Cy Young season in 2015 to just 12% in 2019, and its effectiveness has waned as well; hitters had a .662 slugging percentage against the pitch last year. That number was .266 in his 2015 campaign, and even as recently as his debut season in Philadelphia that number was just .327. Just look at the difference between his 2018 slider and the one he was throwing in 2019:

The 2018 slider wass much crisper, faster and has more movement and the numbers bear this out: in 2018 the slider had 51% more horizontal movement than league average sliders; in 2019 it was 6% below league average.

If Arrieta’s elbow is healed and he’s able to throw a better version of the slider this year, it’s very possible he could put together a solid season. The rest of his secondary pitches were still effective — in 2019 batters slugged .327 against his changeup and .265 against his curve. They did some damage against his favored sinker, slugging .474, but in theory, he would have to rely less on the sinker with a wider selection of secondary pitches at his disposal. It’s not unreasonable to expect some of these offerings to be even more potent now that Arrieta will be throwing pain-free.

The team doesn’t need Jake Arrieta to be a Cy Young-caliber starter this upcoming season— that’s why they have Aaron Nola and why they signed Wheeler. Instead, the team will be looking for a competent, reliable starter to handle a hefty workload and save a mostly unproven bullpen from being overworked. While his age raises some questions about his durability, this will be the healthiest version of Arrieta we’ve seen in his two seasons with the team, and a healthy Arrieta is still capable of producing like a No. 3 starter.

Nick Pivetta

Going into the 2019 season, the dominant storyline regarding the Phillies pitching staff was that this would be Nick Pivetta’s breakout season. He had just completed a solid 2018 campaign and finally seemed to be learning how to harness his overpowering stuff. It seemed as though the team even bought into the hype, making Pivetta the No. 2 starter in the rotation by moving him ahead of Jake Arrieta at the start of the season.

Needless to say, the ensuing results didn’t quite live up to expectations. Pivetta began the season with four bad outings, an 8.35 ERA and a demotion to Triple-A in April. He returned to the Phillies in May and briefly pitched well—including a complete game against the Reds—before faltering again, eventually finishing the year as a reliever. What went wrong?

The strategy du jour for any pitcher with a decent fastball is to have them throw the pitch at the top of the zone and pair that with a wipeout breaking ball at the hitter’s knees; this is the exact strategy that led to a massive breakout for Gerrit Cole and has been suggested for Wheeler. The Phillies began to implement the strategy with most of their pitching staff in 2018 but embraced the philosophy even more last season, especially with Nick Pivetta. When it works, it can be downright overpowering:

However, the potential downside of not executing that plan is costly: if a pitcher doesn’t elevate his fastball enough and leaves it over the middle of the plate, hitters are happy to deposit the ball 400+ feet away in the outfield seats:

This is exactly what happened too many times with Pivetta last year, as his fastball was roughed up to the tune of a .348 average and .697 slugging percentage against. He couldn’t consistently place his pitches up in the zone and these mistakes were punished. CSAA – Called Strikes Above Average – is a statistic on Baseball Prospectus that can be used as a proxy for a pitcher’s command. Pivetta had the second-worst showing in this metric of any pitcher who pitched 90+ innings last season; he clearly had trouble hitting his spots.

Oftentimes a pitcher struggles with his command and control when he isn’t consistent mechanically. Pivetta seems to have addressed this problem in the offseason, recently posting a glimpse at his altered delivery featuring more hip rotation and shorter arm action:

Another popular coaching method that’s taken hold over baseball is having players throw breaking pitches more often, particularly if that pitch is their best offering. Recall Lance McCullers Jr. famously throwing 24 consecutive curveballs in the American League Championship Series in 2017, or Patrick Corbin using his slider much more in 2018 and blossoming into an ace as a result. It appears that former pitching coach Chris Young—himself a member of the Houston staff that encouraged McCullers Jr. to lean on his curve—tried to instill the same approach in Pivetta last year.

After throwing his curve 21.9% of the time in 2018—24th most in the league — his usage of the curve jumped all the way to 35.2% in 2019. He relied on the pitch more than all but five other pitchers last season. It was still mostly effective, but not the same devastating weapon it was for him the previous season. Overuse of that pitch and the sequencing problems that usage caused combined with erratic command seemed to put him in fewer favorable situations:

(CU = Curveball)

	CU Use %	League Rank	CU Swing ing strike %	CU K%	1st pitch fastball %	1^st pitch CU %	0-1 count %	% of 2 strike counts
2018	21.9	24^th	15.4	38.1	60.3	19.9	54.3	59.4
2019	35.3	6^th	11.1	25.6	46.5	34.1	48.9	53.2

An elevated, rising fastball and knee-buckling curve work well in tandem to put away hitters, but only if the pitcher can get to two-strike counts to use them. As you can see from the table above, Pivetta was getting to those two-strike counts much less, and as a result opposing batters had the advantage of waiting for the recurring mistake pitches he threw so often in 2019.

New pitching coach Bryan Price will be tasked with finding the right pitch mix for Pivetta, along with putting together a better overall approach for each plate appearance. A return to a simpler strategy—more four-seamers to get ahead of hitters before using the curve as an out pitch—seems like a good place to start. Combined with (hopefully) better command from improved mechanics, Pivetta may return to being the promising power pitcher that everybody thought he was a year ago.