Stephen Kolek

ActiveIL

Kansas City Royals · SP

Age 296' 3" · 210 lbsThrows Right

#605 Current

FBaseball Overview

This 29-year-old right-hander operates as a depth starter in the Kansas City rotation, offering modest win potential with moderate strikeout upside for fantasy managers willing to accept volatility. Through the first month-plus of 2026, Kolek has posted a 4.15 ERA with a 1.19 WHIP across 52 innings, marking a slight step backward from his solid 3.51 ERA in 2025, though his strikeout rate remains respectable at around 5.9 K/9. His 34 strikeouts this season suggest he can provide streaming value in deep leagues during favorable matchups, but the uptick in ERA and WHIP indicates he remains inconsistent and unreliable as a full-time fantasy asset. Managers should view Kolek as a back-end rotation option or waiver-wire pickup rather than a foundational starter, banking on occasional strong outings while managing the risk of poor performances that have plagued his early tenure.

MLB Pitching

Year	Team	G	GS	W	L	ERA	WHIP	K	IP	BB
2024	San Diego Padres	42	0	3	0	5.21	1.52	39	46.2	12
2025	2 teams▼	19	19	5	7	3.51	1.14	77	112.2	31
2026	Kansas City Royals	10	10	4	3	4.50	1.24	34	54.0	12
Career	Totals	71	29	12	10	4.13	1.25	150	213.1	55

Source: MLB Stats API · Multi-team seasons show combined totals — click to expand

Minor League Pitching

Year	Team	G	GS	W	L	SV	ERA	WHIP	K	IP	BB
2018	2 teams▼	17	0	2	0	3	1.42	0.92	30	31.2	7
2019	Great Lakes Loons	27	25	7	8	0	5.00	1.45	109	131.1	48
2021	3 teams▼	24	9	4	3	0	6.03	1.44	67	59.2	25
2022	Arkansas Travelers	27	27	6	13	0	4.51	1.43	138	143.2	66
2023	2 teams▼	49	1	6	2	4	3.76	1.21	76	69.1	32
2025	2 teams▼	11	11	2	3	0	6.26	1.80	41	46.0	15
2026	Omaha Storm Chasers	5	5	0	1	0	3.32	1.53	17	19.0	4
Career	Totals	160	78	27	30	7	4.64	1.41	478	500.2	197

Source: MLB Stats API · Multi-team seasons show combined totals — click to expand

Last Week / Last Month

Current season · MLB only

7 games

G	GS	IP	W-L	SV	ERA	WHIP	K	BB
7	7	37.0	2-3	0	4.62	1.35	22	8

30 games

G	GS	IP	W-L	SV	ERA	WHIP	K	BB
10	10	54.0	4-3	0	4.50	1.24	34	12

Game Log2026 MLB

Loading game log…

Advanced Stats2026 season · via Baseball Savant

Click for year to year changes

FB Velo94.0 mph

Avg Spin2241 rpm

Whiff %19.8%

K %15.2%

BB %5.4%

Hard Hit %37.4%

Barrel %6.9%

xERA3.87

xBA Against0.262

xSLG Against0.380

BA Against0.262

SLG Against0.448

GB%46.0%

FB%22.7%

What These Stats Mean

FB Velo — Average fastball velocity. Harder throwers generate more swings and misses, setting up every other pitch in their arsenal. Velocity is the foundation of strikeout upside.

Avg Spin — Average spin rate across all pitches. Higher spin creates more movement and makes pitches harder to square up — elite spinners run better strikeout and batting average against numbers.

Whiff % — Swings-and-misses per swing. The most direct measure of a pitcher's ability to miss bats and the best leading indicator of strikeout rate.

K % — Strikeout rate per batter faced. The core fantasy pitching stat — high K% means reliable strikeout totals that hold up even in shorter starts.

BB % — Walk rate per batter faced. The primary control metric. High BB% tanks ERA and WHIP and keeps baserunners on constantly. Elite starters typically run below 7%.

Hard Hit % — Percentage of batted balls hit 95 mph or harder against. Low hard-hit% means weak contact, protecting both ERA and the defense behind the pitcher.

Barrel % — Percentage of batted balls barreled against. The most direct home run predictor — low barrel% pitchers rarely give up long balls.

xERA — Expected ERA based on contact quality allowed, removing the effect of sequencing, luck, and defense. Better predictor of future ERA than ERA itself.

xBA Against — Expected batting average opponents should hit based on contact quality. A gap between xBA and actual BA indicates unsustainable luck in either direction.

xSLG Against — Expected slugging allowed based on contact quality. High xSLG against predicts future extra-base damage; low xSLG means the pitcher is genuinely suppressing power.

BA Against — Actual batting average opponents are hitting — a key WHIP component. Check xBA to see if the number is sustainable.

SLG Against — Actual slugging allowed. Captures hits, doubles, triples, and home runs — lower means the pitcher is limiting the power damage he gives up.

GB% — Ground ball rate. High GB% pitchers generate double plays, limit home runs, and keep the ball in the park — great for protecting ERA and WHIP ratios.

FB% — Fly ball rate. High FB% pitchers give up more air contact — dangerous when combined with high exit velocity, less so when contact is soft.

Loading player data...

Year

Team

ERA

WHIP

2024

San Diego Padres

5.21

1.52

46.2

2025

2 teams▼

3.51

1.14

112.2

2026

Kansas City Royals

4.50

1.24

54.0

Career

Totals

4.13

1.25

150

213.1

Year

Team

ERA

WHIP

2018

2 teams▼

1.42

0.92

31.2

2019

Great Lakes Loons

5.00

1.45

109

131.1

2021

3 teams▼

6.03

1.44

59.2

2022

Arkansas Travelers

4.51

1.43

138

143.2

2023

2 teams▼

3.76

1.21

69.1

2025

2 teams▼

6.26

1.80

46.0

2026

Omaha Storm Chasers

3.32

1.53

19.0

Career

Totals

160

4.64

1.41

478

500.2

197

W-L

ERA

WHIP

37.0

2-3

4.62

1.35

W-L

ERA

WHIP

54.0

4-3

4.50

1.24