Statcast Fastball Usage Studs and Duds for Week 19

Welcome back to RotoBaller’s pitchers advanced stats and StatCast studs and duds article series! Each week we will select an advanced stat, choose two studs and two duds, and analyze what those stats could mean for future fantasy output. This week I will be using Statcast's pitch arsenal tab to look at starters' four-seam fastball usage.

The fastball is most pitcher's go-to pitch, yet it is more common to see relievers rely heavily on the pitch than starters. An overpowering fastball can be key to strong strikeout rates, a metric that is quite important to fantasy players, so it is worth identifying those starters who can succeed with high fastball usage.

I will pick two high-volume fastball pitcher who have done relatively well this season and two who have not or are slumping recently. I will not just be focusing on big-name guys, but also potential waiver-wire streamers given how far we are into the season. That being said, let's dive in!

Four-Seam Fastball Studs

All stats current as of 8/6/19, courtesy of Baseballsavant.com 

Vince Velasquez - Philadelphia Phillies

64.2% fastball usage

Our first pitcher has been a fantasy disappointment for several seasons now, thought to be a potential stud because of his fastball but failing to become one because of his lack of command. Vince Velasquez has been more consistent this season, compiling a 4.23 ERA over 14 starts. He has been even better lately, posting a 3.29 ERA and 25% K rate over his last five starts. Velasquez has one of the highest four-seamer usages among starters who have thrown at least 500 pitches this season, and at just 18% ownership in Yahoo leagues, could he be a worthwhile streamer?   

Velasquez relies so much on his fastball because it is a pretty good one. Both its velocity (94.4 MPH) and spin rate (2,382 revolutions per minute) are in the top 30% of baseball, leading to a 12.4% swinging-strike rate with the pitch. Further, he has allowed a .219 batting average against with the pitch and a .232 expected batting average.

Velasquez's command hasn't been all that much better on the season (1.35 WHIP) but he has been able to find it lately. His WHIP has fallen in his last five starts (1.21), which is key to finding success with the fastball. His 4.28 SIERA in those starts suggests that he has over-performed, but he has been consistent over that time period regardless.

I think that Velasquez is a nice streaming option down the stretch. His good fastball makes him a strikeout threat and he won't hurt you in ERA as long as his command is decent. Pair his fastball with a competitive offense supporting him and you have a sneaky bench pitcher who you can use to take advantage of favorable matchups.

Chris Paddack - San Diego Padres

60.1% fastball usage

Our second pitcher caused a lot of hype in dynasty leagues as a top target and he has delivered. 23-year-old rookie Chris Paddack has a stellar 3.19 ERA and 0.93 WHIP with a 26.4% K rate in 104 1/3 innings pitched this season. He has found success with a three-pitch arsenal, over half of it coming from his fastball. Let's take a look at how Paddack has found his success.

Paddack's fastball is a nice pitch (9.6% swinging-strike rate, .189 batting average against) but it isn't all that overpowering. It only comes in at 93.9 MPH with a 2,231 revolution-per-minute spin rate. The reason it is as successful as it is his devastating changeup that he pairs with it. Paddack throws his changeup 29.3% of the time and has generated a 17.4% swinging-strike rate. By implementing a classic change-of-speeds approach, Paddack has been immensely successful. 

Paddack's peripherals and underlying stats have all been great this season. He is a legitimate higher-end fantasy option, thanks to his great command and ability to keep hitters off-balance. His use of the fastball works because of his changeup and he is a great fantasy asset down the stretch; just watch out for a potential innings cap.

Four-Seam Fastball Duds

All stats current as of 8/6/19, courtesy of Baseballsavant.com 

James Paxton - New York Yankees

63.1% fastball usage

Our third pitcher has been a disappointment all season long. James Paxton has a mediocre 4.61 ERA and 1.46 WHIP over 95 2/3 IP this season. His 29.5% strikeout rate has been impressive, thanks in part to his high fastball usage, but his command has not been. Fantasy owners did not bargain for this output, so is there any hope he can improve over the last two months of the season?

The big thing for Paxton has been his lack of command. He has a potentially-overpowering fastball at 95.4 MPH with an 11.6% swinging-strike rate, but as the old saying goes, the harder a pitch comes in, the harder it goes out. Paxton has allowed a .305 batting average against with the pitch and has a poor batted-ball profile overall (89.4-MPH average exit velocity, 39.8% hard-hit rate, 17.9-degree launch angle). This batted-ball profile does not bode well in Yankee Stadium and it has shown. The one bit of hope is Paxton's 3.94 SIERA, but, given how bad his batted-ball profile is, I am not optimistic that his ERA would regress all that much.

Fantasy owners don't really have much of a choice with Paxton at this point. They drafted him as a top pitcher and he simply hasn't delivered. His strikeout numbers have been good, but his fastball hasn't been enough to succeed. I would consider picking matchups wisely down the stretch.

Jake Odorizzi - Minnesota Twins

57% fastball usage

Our final pitcher has had a solid season to this point, posting a 3.61 ERA, 1.19 WHIP, and 25.4% K rate. Jake Odorizzi has been putting it all together this season, all the while relying heavily on his four-seamer (57% usage), and even more so on fastballs in general (92.1% usage of four-seamer, cutter, and split-finger). However, Odorizzi has a bloated 5.19 ERA in his last five starts. How has Odorizzi managed to be so successful despite relying so much on his fastball and can he sustain it?

Odorizzi's four-seamer isn't overpowering (92.9 MPH, 2,237 revolutions per minute), but he has managed to post a 12.8% swinging-strike rate with the pitch on the season. It may appear that he is in danger of having that catch up to him based on his last five starts. However, Odorizzi has actually pitched quite well in four of those five starts; his numbers are thrown off by one bad start against the Yankees in which he allowed nine earned runs.

As the fantasy season gets closer to the playoffs, owners tend to fixate on a pitcher's last start or two as they seem to hold more weight. However, it is important to believe in the big picture. Odorizzi has pitched well with his fastball-heavy approach thanks to his improved command. If he has helped fantasy owners this far, now is not the time to abandon hope just because of one poor start. Despite what you may think, Odorizzi is not actually a fastball dud; use him with confidence going forward.