Strikeout Rate Risers and Fallers - Buy or Sell for Week 18

Welcome back to the strikeout rate risers and fallers series for Week 18! Each week we will take a look at two K% risers and two fallers, analyze what is behind those changes, and then decide if they are actionable. A pitcher can best control their fate by generating swings and misses, so this exercise holds particular importance for fantasy value. Understanding strikeout trends and the stats behind them can help you sort through all the noise and determine which pitchers are legit and which pitchers should be avoided.

The players in this article were chosen using RotoBaller’s K% Risers and Fallers premium Tool. This tool identifies players who are surging and falling in strikeout percentage over the last 30 days. The goal of this tool is to help you find pitchers who are showing improving or declining K%.

Many leagues are quickly approaching the trade deadline, so there isn't much time left to take advantage of buy-low and sell-high opportunities. For this article, I will focus on pitchers who could be particularly moveable for fantasy. Let's get going!

Strikeout Rate Risers

All stats current as of Sunday, July 28

Ryan Yarbrough - Tampa Bay Rays

Season K%: 19.7%, Last 30 Days: 26.7%

Our first K rate riser made a name for himself as a sneaky "relief" pitcher who could rack up wins and has continued to perform in 2019. Ryan Yarbrough has gone 9-3 with a 3.78 ERA and 0.93 WHIP this season, serving as both a starting pitcher and as a follower for the Rays. He has become a fixture in their "rotation" and will likely be relied on even further with the Rays' recent pitching injuries. His season K rate isn't anything special, but he has increased that number over the past 30 days. Is Yarbrough an under-the-radar value for fantasy players?

Yarbrough doesn't have overpowering stuff; his cutter and sinker sit at just 84.6 and 88.3 MPH. However, his secondary pitches are pretty good swing-and-miss options. His changeup (24.9% usage) has a 16.8% swinging-strike rate and his curveball (12.9% usage) has a 14.1% swinging-strike rate. The main reason he manages to strike as many hitters out as he does is his superb command. Yarbrough rarely walks batters (3.8% walk rate) and can command the zone well as indicated by his low WHIP.

In terms of his recent K rate spike, Yarbrough has simply taken advantage of a string of favorable starts. He has posted an impeccable 1.14 ERA with nearly a strikeout per inning in his last five outings, which came against the Twins, the Blue Jays, the White Sox, and the Orioles twice. Regardless, Yarbrough has pitched well all season and should continue to help out fantasy players without always counting as a start. He is definitely worth trying to acquire before the trade deadline passes.   

Matthew Boyd - Detroit Tigers

Season K%: 32.1%, Last 30 Days: 38.2%

Our second K rate riser caused quite the hubbub at the beginning of the season due to his hot start and high strikeout numbers. Matthew Boyd still has an impressive 32.1% K rate on the season, and that mark has jumped to 38.2% in the last 30 days, but he also now has a pedestrian 4.07 ERA. Boyd has been a tougher one to figure out this season, so what should fantasy owners expect from him for the rest of the season? 

Boyd's last five starts have their positives and negatives. The positive is that he has been striking batters out like crazy. Three of those starts had double-digit strikeouts, thanks to an increase of use of his deadly slider (18.8% swinging-strike rate). Boyd has used the pitch 41.6% of the time in July compared to 37% on the season.

The negative is that Boyd has gotten lit up when batters have made contact. He owns a 5.46 ERA and .348 BABIP over those starts. However, Boyd's SIERA over those starts has been a sterling 2.71, suggesting that he has been getting unlucky. His high BABIP compared to a .315 season mark also supports this notion.

Boyd may actually be a good buy-low candidate at this time. His overall season numbers now don't look all that special and his ERA has been ugly over the past 30 days. Despite this, his numbers under the hood tell a different story. If fantasy players could manage to get him from a worried owner, he would be a huge asset for teams down the stretch.

Special mention to Pittsburgh Pirates' Chris Archer, who is once again a top K rate riser this week and would be a solid buy-low target. Also a mention for New York Mets' Zack Wheeler, who is a K rate riser but would be a sell-high candidate given his overall poor performance.

Strikeout Rate Fallers

All stats current as of Sunday, July 28

Jake Odorizzi - Minnesota Twins

Season K%: 25.5%, Last 30 Days: 20.2%

Our first K rate faller has had a good season to this point, posting a 3.84 ERA, 1.20 WHIP, and 25.5% K rate. However, Jake Odorizzi has stumbled lately, posting a bloated 8.34 ERA with a pedestrian 20.2% K rate over his last five starts. I called him a buy-low candidate earlier in the season, but is this still the case?

The main thing that stands out over Odorizzi's last six starts has been his lack of command. His 1.68 WHIP has affected all aspects of his game; his BABIP (.302), walk rate (10.6%), and HR/9 rate (3.18) have all suffered, leading to his poor ERA. Consequently, he has only racked up more than three strikeouts twice in that period. His 5.27 SIERA also supports that he has lacked the control he has had the rest of the season.

This is the second straight week that I have written similar analyses on Odorizzi, but he has had solid control, high strikeout numbers, and a decent batted-ball profile for the majority of the season. I would think that Odorizzi could find his command soon enough, but I'm not as confident in him returning the value I thought he would earlier in the season. He is still worth a shot at a buy-low offer, but I wouldn't give up too much for him at this point.

Masahiro Tanaka - New York Yankees

Season K%: 20.1%, Last 30 Days: 15.5%

Our second K rate faller plays on one of baseball's biggest stages but has not impressed this season. Masahiro Tanaka has a below-average 4.79 ERA, 1.25 WHIP, and a career-low 20.1% K rate. That mark has fallen further over the past 30 days. His overall numbers are not encouraging, but Tanaka has been a strong fantasy asset over the course of his career. Is now the opportunity to buy low on him?

Cutting to the chase, all signs point to no on this one. Tanaka has been awful his last five starts, posting an enormous 11.69 ERA and 1.84 WHIP. He has faced tough matchups (the Rockies, the Rays, and the Red Sox twice), but he will continue to face tough teams during inter-division play down the stretch. His 5.29 SIERA is much better than his ERA for that time, but there is no evidence to suggest that Tanaka has any upside to offer.

At this point, fantasy players may have the option of claiming Tanaka off of waivers if he continues to pitch this poorly. Fantasy owners will just have to hope that he can figure things out quickly. He would be worth a team's last bench spot given his career numbers and potential upside, but I wouldn't offer anything more than my last bench player for him at this time.

Special mention to Milwaukee Brewers' Brandon Woodruff and Baltimore Orioles' John Means, who are both K rate fallers and both on the IL but are good buy-low stash options for deeper, competitive teams.

K-Rate Risers and Fallers - Premium Tool

Identifying top strikeout rate risers and fallers for each week can help you spot the best pickups before your competition. RotoBaller's Premium K-Rate Risers and Fallers tool has you covered every day. As thoughtful fantasy baseball players, we won't lead you astray. This tool will soon be active once we have a large enough sample size in the season to be considered reliable.

This type of data is available as part of our Premium MLB Subscription. Don't settle for basic stats and surface-level advice from other sites. RotoBaller brings you advanced statistics and professional analysis that you need to win your fantasy leagues and DFS games, because we're ballers just like you. We are your secret weapon!

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