Don't have an account?
Join the Best Live Fantasy Chat Community!

Lost password? [X]

Receive free daily analysis:


Already have an account? Log in here.


Forgot Password


Statcast Pitcher Risers/Fallers - RP Trade Candidates (Week 17)

Welcome back to Rotoballer's series using Statcast to extrapolate, dig into, and commiserate over data to examine pitching performances. The weekly series will be dynamic as we fine-tune our findings and enlighten ourselves on the information and tools at our disposal.

We've rolled over the All-Star break and the trade deadline is fast approaching. With myriad players likely on the move over the next week, we'll shift gears in Week 17 and look at baseball's most coveted and reliable commodities, relief pitchers. Our Statcast series has focused solely on starting pitchers, but we'll hop on the trade bandwagon to review which relievers are ones to target or avoid.

The Statcast metric we'll use is a familiar one, xwOBA and its differential to wOBA. In our qualified pool of 64 relievers, the median xwOBA is .287. Real-life trade potential will be assigned marginal credit, as most relievers provide standalone fantasy value regardless of save opportunities. Our in-depth candidates are currently closers, but the collection of "other" players could also be keen pickups and drops to protect multiple pitching categories down the stretch.

Editor's Note: Get any full-season MLB Premium Pass for 50% off, with exclusive access to our season-long articles, 15 in-season lineup tools and over 200 days of expert DFS research/tools. Sign Up Now!


Relievers to Target

All stats as of July 24 for 64 relief pitchers with a minimum of 150 plate appearances against.

Wade Davis, Colorado Rockies (4.61 ERA, 1.22 WHIP, 9.88 K/9, 28 Saves)

Wade Davis is fresh off a five-run implosion against the Astros on July 24 so the timing on this bullish call is impeccable. Davis has a passable .273 xwOBA but the .024 differential against his wOBA (.297) is ninth-widest amongst relievers. With the Rockies in the thick of another NL West race, Davis is likely a fixture in Colorado for the rest of 2018.

Davis has endured a relatively rough season, highlighted by career-high hard contact (33.3%) and walk rates (4.61 BB/9), but he's trending positively. Prior to the aforementioned meltdown, Davis had allowed only two earned runs in his last 12 outings (1.50 ERA), posting a 0.75 WHIP and 9.75 K/9 along the way. While his dominant cutter has retreated this year, opponents are slugging a measly .143 against the pitch in July. Davis struggled in May and June, but pitch effectiveness for his fastball-cutter combination is starting to normalize in-line with career averages.

Before the transitory swoon, Davis enjoyed a fantastic April in his Rockies debut (2.61 ERA, 0.87 WHIP). Walks appear the determinant factor to his second-half success. Improve location and he should succeed in setting up the killer cutter. Davis could likely be nabbed at a discount in fantasy leagues, a reversion to the lockdown reliever of the past four years seems just around the corner.

Brad Boxberger, Arizona Diamondbacks (2.89 ERA, 1.15 WHIP, 12.54 K/9, 24 Saves)

Lifetime reliever Brad Boxberger has embraced his first year as a full-time closer, pacing better than career trends in ERA, strikeouts and walks. Boxberger sits in the top-15 in xwOBA (.268) yet also experiences an unfavorable delta of .009 compared to his wOBA (.277). Similar to Davis, Boxberger and the D-Backs are entrenched in a tight pennant race, securing his season-long closer value.

Dissimilar to Davis, Boxberger has been a model of consistency. Excluding a four-run debacle on June 17 against the Mets, he has given up only eight earned runs this season. The blip hasn't phased the veteran, Boxberger is registering a .040 BAA and 0.50 WHIP in eight July appearances. The key change in Boxberger's approach in 2018 has been the abandonment of a previously terrible slider. He's narrowed his arsenal to a pure fastball-changeup combination which has diminished the risk of unwanted meatballs. Boxberger has maintained a steady 12 MPH differential between the two pitches, generating strong whiff rates and positive pitch values for both.

Naysayers can point to Boxberger's FIP (3.99) and BABIP (.244) to question his worth. A 44.0% Hard% could be concerning, but the damage has been limited to worm burners (51.2% GB%). It's not farfetched to imagine he'll encounter a handful of slipups to reconcile the ERA and FIP disparity, but the dependable save chances and strikeouts should play in any league.

Other attractive relievers: Zach Duke (MIN, .049 wOBA/xwOBA differential), Ryan Tepera (TOR, .034), Shane Greene (DET, .020)


Relievers to Avoid

Raisel Iglesias, Cincinnati Reds (2.20 ERA, 0.98 WHIP, 9.40 K/9, 19 Saves)

Despite a very strong season to-date, Raisel Iglesias rings the alarm bells with a .321 xwOBA that's .065 points higher than his wOBA (.256). That gap is the third-most fortuitous in our reliever pool. Ignoring outstanding trade rumors, we'll observe Iglesias' pitcher-specific attributes for clues on his future performance.

Iglesias' success this season could be credited to the establishment of a phenomenal changeup to pair with his fastball-slider. He's upped the changeup mix to 22% this season, inducing a 26% whiff rate on the pitch and lifting his overall SwStr% to a career-best 15%. However, Iglesias has been losing velocity on all his pitches since May. While the change and slider have yet to show ill effect, Iglesias has been grooving more fastballs causing a jump in opponent slugging from .435 to .714 since May. Without a potent fastball, overall pitch effectiveness is at risk of broad deterioration.

While Iglesias rarely surrenders hard contact (34.8%), his 7.1% barrel rate is above average resulting in structurally elevated LD% (24.1%) and HR/FB (15.0%) tendencies. Iglesias also benefits from extremely lucky factors like LOB% (92.9%) and BABIP (.217). He's generating swings-and-misses, but the career-low K/9 doesn't support his ninth-best strand rate for relievers. Fantasy managers with pitching flexibility should consider him a frontline trade candidate to obtain other needs.

Blake Treinen, Oakland Athletics (1.06 ERA, 0.98 WHIP, 11.47 K/9, 25 Saves)

We touted Blake Treinen in the offseason as a sleeper and he's exceeded all reasonable expectations. Before we delve into Treinen's possible downfall, let's establish that the call is relative. Although he holds the sixth-best xwOBA of .252, his .205 wOBA is .047 points lower and ranks sixth-most favorable amongst relievers.

Treinen has ridden obnoxious 98 MPH fastballs and sinkers to excellent pitch values across his repertoire this season. However, line drives against the sinker has ticked up to 27% in July, leading him to deemphasize the pitch and lean more on his cutter. Said cutter is Treinen's worst pitch but he's increased its usage from 5% to over 10%. While Treinen's overall resume remains outstanding, the change in approach is at least puzzling and at worst a possible mechanical glitch for the All-Star.

Treinen's success is rooted in his ability to avoid sweet spots (1.4% Barrels/PA). But considering his low fly ball ratio (26.2%), the 3.1% HR/FB appears artificially low. Make no mistake, Treinen is having a breakout season and the A's competitiveness only solidifies his fantasy standing. But, those same elements that make him so attractive also inflate his trade value. No matter the talent, it's unusual for a pitcher's xwOBA and wOBA to remain disconnected. There could be no better time to reap top dollar from a team desperate for Treinen's services.

Other risky bullpen arms: David Robertson (NYY, -.041 wOBA/xwOBA differential), Kelvin Herrera (WAS, -.032), Joakim Soria (CHW, -.023)


More Sabermetrics & Fantasy Baseball Strategy

More Recent Articles


FAAB Bidding - Week 11 Waiver Wire Targets

Assisting our famous waiver wire pickups list, and our weekly waiver wire columns by position, this column focuses on suggested waiver wire bidding percentages for fantasy football owners in leagues using a Free Agent Acquisition Budget (FAAB). As a caveat, these prices do not by any means indicate how much these free agent players will... Read More

Week 11 Waiver Wire Pickups & Adds

It's crunch time, with precious few games left before the fantasy regular season ends. There aren't many new names emerging on the waiver wire at this juncture but the RB situations in Atlanta and Detroit bear watching, while the Jets passing game has shown signs of life. No, really. Each week, we will advise you... Read More

Deeper League Free Agent Pickups for Week 11

Rotoballers, if you're not active on the waiver wire this time of year, there are only two reasonable explanations: 1) You're sitting at 3-7 (or worse) and don't find it enjoyable to play spoiler to your league mates, or 2) You're 8-2 (or better) and have nothing but matchup-proof studs on your starting lineup and... Read More

Week 11 Defense (DEF) Streamers and Starts - 2019 Fantasy Tiers, Rankings

Below are RotoBaller's Week 11 defense tiers and rankings, or which defenses to stream, start and target off the waiver wire for Week 11 of the NFL and fantasy football season. In case you missed it, this is our seventh year now writing this weekly column. Our weekly tiered defense rankings are a guide to making waiver... Read More

Week 11 Kicker Streamers and Starts - 2019 Fantasy Tiers, Rankings

It's Week 11, and we're getting closer and closer to the fantasy football playoffs. The consistent options are getting more and more clear, especially at the kicking position. We're also going to start dealing with everyone's favorite factor, which is inclement weather, especially up north. The margin for error in these weeks is slim, and... Read More

Week 10 Surprises? We Must Overreact Immediately!

In Week 10, Christian Kirk, Darius Slayton, Tyreek Hill, and Michael Thomas all had beatable cornerback matchups and finished as the top-four wide receivers in PPR scoring. At running back, Derrick Henry exploited a poor Chiefs run defense and rumbled for 188 yards and two touchdowns, finishing as the No. 1 running back on the week. Ronald... Read More

The Cut List - Players on the Chopping Block (Week 11)

This is your weekly list of players to drop. I will do my best to limit this list to injured players and players you might consider holding. If you roster pure handcuffs or backups, obviously you can let them go at any time. The players on this list will, ideally, be guys that aren't clearly... Read More

Running Back Waiver Wire Pickups - Week 11

The regular season continues to advance at a relentless pace as we have now entered the planning process for Week 11. Some of you are in the favorable position of only needing slight modifications to rosters that are destined to enter the fantasy playoffs. But many of you are still searching for the most effective... Read More

Wide Receiver Waiver Wire Pickups - Week 11

Did you survive the terrible, no good, very bad six-team bye week? If so, welcome to the other side, when roster building gets slightly easier going forward. If not, I'm sorry, but you still have time to get things back on the right path. Let's talk about some wide receivers who might be able to... Read More

Week 11 Tight End Waiver Wire Picks and Streamers

If your fantasy football squad is still in the playoff hunt heading into Week 11, then congratulations on not being the Pat Shurmur or Freddie Kitchens of your league. Fantasy football players will have to live without New York’s Evan Engram, Green Bay’s Jimmy Graham and Tennessee’s Jonnu Smith as their teams are on bye.... Read More

Quarterback Waiver Wire Pickups and Streamers - Week 11

We've got plenty to unpack at the quarterback position following an exciting Week 10. While no major injuries occurred in game, the revelation of Matthew Stafford's back injury was quite a surprise and left some owners scrambling just before lineups locked. So the year of the backup continued this week, as 16 of the 32... Read More

Waiver Wire Express - Week 11 Lightning Round

With 10 weeks down and only a few more weeks of the fantasy regular season to go, your vision for the playoffs should be coming into focus. The Giants, Packers, Seahawks and Titans are on bye -- with the Cardinals, Chargers, Chiefs and Vikings in Week 12 to round out the weekly vacations. To help... Read More

Fantasy Football Waiver Wire Pickups List

Back by popular demand in 2019... RotoBaller has brought back for the NFL season our Ultimate 2019 Fantasy Football Sleepers and Waiver Wire Pickups List.  Be sure to also try our other lineup tools below. Using your phone? Be sure to also download our free app which includes news, notifications, injury alerts & articles.   Rankings WizardWeekly... Read More

Week 10 Start/Sit: Monday Night Football Matchups Analysis

We got a good one on Monday night folks. Both for the NFC West division and, more importantly, for fantasy. Two of the top teams in the NFL matchup at Levi's Stadium. We can finally find out if the 49ers are for real, or if they were just beating up on bad teams all season.... Read More

Week 10 Fantasy Football Staff Rankings

Below you will find all of RotoBaller's fantasy football weekly rankings, tiers, player news and stats for the 2019 NFL season. Our Ranking Wizard displays our staff's rankings for various league formats, all in one easy place. Here's what you'll find: Weekly PPR Rankings Weekly Half-PPR Rankings Weekly Standard Rankings Dynasty League Rankings     Fantasy... Read More