K+GB% is the number of strikeouts (K%) plus the number of ground balls (GB%) hit over the total number of plate appearances.
It is one of the best indicators for how successful a pitcher should be, as it is correlated with xFIP.
xFIP is perhaps the single best future ERA indicator, and it is used often in the fantasy baseball community. It weighs strikeouts and ground balls heavily (it actually weighs flyballs heavily, but since groundballs are the opposite of flyballs, it technically factors it in).
If we as fantasy players are chasing xFIP, we need to chase K+GB% to a certain extent as well.
Here are the Top 5 K+GB% pitchers from 2019:
Luis Castillo is one of the more liked pitchers by the fantasy community. An example as to why, he led the majors in K+GB% among pitchers who pitched a minimum of 100 innings.
Castillo had the best changeup in the game, and it is the reason he sat on the throne for this statistic. The pitch induced a ridiculous 277 whiffs, good for a 27.8% swinging-strike rate, a 48.0% whiff rate, and a 58.5% groundball rate.
Castillo can quickly raise his strikeout rate, as he has the arsenal to get above 30% with three borderline dominant pitches. If he can reach that ceiling, he can become a near 90% K+GB% pitcher.
Strasburg altered his pitch mix in 2019, throwing his curveball, changeup, and two-seam fastball more than any year prior. It led to a near 8% increase in his GB rate, while maintaining his career average in strikeout rate.
His curveball finished 3rd overall in poorly/topped + poorly/weak contact, only trailing Adam Wainwright and Charlie Morton. His changeup was the other devastating pitch, which finished top 20 in the league in groundball rate, and poorly/topped pitches.
Armed with perhaps the best off-speed tandem in baseball, Strasburg is a safe bet to stay in the elite tier of the K+GB% leaderboard.
Cole is a below-average groundball pitcher, as he finished 71stin GB% out of the 113 qualified pitchers. The reason he finished 3rd overall is because of his ridiculous 39.9 K%, which lead the next qualified pitcher by over 4%.
His four-seam fastball is one of the most dominant pitches in baseball, leading the majors with a 19.8% swinging-strike rate, and a 37.6% whiff rate.
Cole has moved to New York from Houston, but there is no reason to doubt that his K% will remain among the best in baseball.
Gray rejuvenated his career in 2019 after an up-and-down prior 3 seasons.
He has sat above a 50% groundball rate every season he has been in the majors. He changed his pitch mix in 2019, and it led to a spike in strikeouts to go with an already solid groundball rate. He did so by increasing his curveball and slider usage, which also happen to be his two best pitches.
Unless Gray reverts back to throwing his two-seam fastball more (there is no reason to think he will), expect him to remain among the league leaders in K+GB%.
Keuchel is this list for one reason, and one reason only, he is the best groundball pitcher in baseball.
He led the majors in 2019 with a 60.1% groundball rate, 3.2% above the next closest starter. It was the 4th time in 6 years that Keuchel eclipsed a 60% or better groundball rate, which is rare territory.
As awesome as he is at getting groundballs, he is the polar opposite in throwing strikeouts. His 18.7% strikeout rate ranked 89th out of 113 pitchers. Most do not view pitchers with low strikeout rates as dependable, but when you induce as many groundballs as Keuchel, he is a safe option in the later portion of drafts for decent ratios and wins.
The rest of the top 30 K+GB% starting pitchers with a minimum of 100 innings pitches:
Notable non-qualified starters with over 30 innings pitched and 70% K+GB%:
*** All statistics were pulled from fangraphs, and baseball savant’s search page, and then filtered by me.