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Ryan Zeferjahn

Position: Pitcher

Bats: Right • Throws: Right

6-5, 209lb (196cm, 94kg)

Born: February 28, 1998 in Topeka, KS us

Draft: Drafted by the Tampa Bay Rays in the 37th round of the 2016 MLB June Amateur Draft from Seaman HS (Topeka, KS) and the Boston Red Sox in the 3rd round of the 2019 MLB June Amateur Draft from University of Kansas (Lawrence, KS).

High School: Seaman HS (Topeka, KS)

School: University of Kansas (Lawrence, KS)

Rookie Status: Still Intact through 2025

2025 Contract Status: Pre-Arb Eligible

Service Time (01/2025): 0.038 • Arb Eligible: 2028 • Free Agent: 2031

Full Name: Ryan Joseph Zeferjahn

Pronunciation: \ZEFF-er-john\

Instagram: @ryanzeferjahn13

View Player Info from the B-R Bullpen

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SUMMARY

2025

Career

WAR

0.1

0.6

ERA

4.73

3.26

13.1

30.1

WHIP

1.275

0.989

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Year	Age	AgeDif	Tm	Lg	Lev	Aff	W	L	W-L%	ERA	RA9	G	GS	GF	CG	SHO	SV	IP	H	R	ER	HR	BB	IBB	SO	HBP	BK	WP	BF	WHIP	H9	HR9	BB9	SO9	SO/W
2017	19	-1.5	Kansas	B12	NCAA		4	4	.500	6.19	6.36	18	13		0	0	0	52.1	58	37	36	4	35	0	53	7	0	12	248	1.777	10.0	0.7	6.0	9.1	1.51
2017	19	-1.0	Falmouth	CCBL	Smr		0	0		2.40	2.40	13	0	9	0	0	6	15.0	5	4	4	1	9	1	20	0	0	2	58	0.933	3.0	0.6	5.4	12.0	2.22
2018	20	-0.6	Kansas	B12	NCAA		8	5	.615	4.48	4.82	14	14		1	0	0	80.1	66	43	40	11	39	0	100	17	1	14	354	1.307	7.4	1.2	4.4	11.2	2.56
2019	21	0.4	Kansas	B12	NCAA		5	2	.714	3.97	4.38	15	15		0	0	0	88.1	60	43	39	7	44	1	107	16	1	5	378	1.177	6.1	0.7	4.5	10.9	2.43
2019	21	-0.3	Lowell	NYPL	A-	BOS	0	2	.000	4.50	4.91	12	12	0	0	0	0	22.0	24	12	11	2	12	0	31	3	0	2	101	1.636	9.8	0.8	4.9	12.7	2.58

2021	23		2 Teams	2 Lgs	A-Rk	BOS	1	4	.200	5.98	7.60	16	16	0	0	0	0	55.2	65	47	37	4	18	0	59	3	0	6	250	1.491	10.5	0.6	2.9	9.5	3.28
2021	23	1.1	Salem	LAE	A	BOS	1	4	.200	6.91	8.86	12	12	0	0	0	0	41.2	53	41	32	2	15	0	41	2	0	4	194	1.632	11.4	0.4	3.2	8.9	2.73
2021	23	2.2	Red Sox	FCL	Rk	BOS	0	0		3.21	3.86	4	4	0	0	0	0	14.0	12	6	5	2	3	0	18	1	0	2	56	1.071	7.7	1.3	1.9	11.6	6.00
2022	24		2 Teams	2 Lgs	A+-AA	BOS	5	4	.556	5.05	5.30	34	5	6	0	0	1	71.1	61	42	40	7	33	0	80	9	2	10	305	1.318	7.7	0.9	4.2	10.1	2.42
2022	24	-0.5	Portland	EL	AA	BOS	3	0	1.000	0.84	0.84	6	0	0	0	0	0	10.2	3	1	1	1	4	0	7	1	0	0	37	0.656	2.5	0.8	3.4	5.9	1.75
2022	24	1.0	Greenville	SALL	A+	BOS	2	4	.333	5.79	6.08	28	5	6	0	0	1	60.2	58	41	39	6	29	0	73	8	2	10	268	1.434	8.6	0.9	4.3	10.8	2.52
2022	24	0.8	Scottsdale	AZFL	Fal		0	1	.000	4.80	6.00	9	1	0	0	0	0	15.0	11	10	8	2	8	0	18	1	0	2	64	1.267	6.6	1.2	4.8	10.8	2.25
2023	25		2 Teams	2 Lgs	AA-A	BOS	1	4	.200	4.70	5.28	36	1	11	0	0	2	46.0	36	27	24	7	40	0	70	6	0	4	216	1.652	7.0	1.4	7.8	13.7	1.75
2023	25	0.6	Portland	EL	AA	BOS	0	4	.000	5.02	5.65	34	0	11	0	0	2	43.0	33	27	24	7	40	0	68	6	0	4	204	1.698	6.9	1.5	8.4	14.2	1.70
2023	25	3.4	Salem	CARL	A	BOS	1	0	1.000	0.00	0.00	2	1	0	0	0	0	3.0	3	0	0	0	0	0	2	0	0	0	12	1.000	9.0	0.0	0.0	6.0
2024	26		3 Teams	3 Lgs	AA-AAA	LAA	1	3	.250	3.33	4.30	30	1	17	0	0	7	46.0	34	22	17	4	21	1	61	6	1	2	197	1.196	6.7	0.8	4.1	11.9	2.90
2024	26	-1.0	Worcester	IL	AAA	BOS	0	3	.000	5.47	6.57	18	1	12	0	0	4	24.2	20	18	15	3	17	1	31	6	1	1	115	1.500	7.3	1.1	6.2	11.3	1.82
2024	26	-1.5	Salt Lake	PCL	AAA	LAA	0	0		2.35	2.35	5	0	2	0	0	0	7.2	5	2	2	1	1	0	8	0	0	0	28	0.783	5.9	1.2	1.2	9.4	8.00
2024	26	1.5	Portland	EL	AA	BOS	1	0	1.000	0.00	1.32	7	0	3	0	0	3	13.2	9	2	0	0	3	0	22	0	0	1	54	0.878	5.9	0.0	2.0	14.5	7.33
2024	26	-3.0	LAA	AL	Maj	LAA	0	0		2.12	2.12	12	0	4	0	0	0	17.0	7	4	4	0	6	1	18	2	0	0	64	0.765	3.7	0.0	3.2	9.5	3.00
2025	27	-2.4	LAA	AL	Maj	LAA	2	0	1.000	4.73	4.73	16	0	1	0	0	1	13.1	11	7	7	2	6	0	23	0	0	1	57	1.275	7.4	1.4	4.1	15.5	3.83
Year	Age	AgeDif	Tm	Lg	Lev	Aff	W	L	W-L%	ERA	RA9	G	GS	GF	CG	SHO	SV	IP	H	R	ER	HR	BB	IBB	SO	HBP	BK	WP	BF	WHIP	H9	HR9	BB9	SO9	SO/W
Majors (2 seasons)					Majors		2	0	1.000	3.26	3.26	28	0	5	0	0	1	30.1	18	11	11	2	12	1	41	2	0	1	121	0.989	5.3	0.6	3.6	12.2	3.42
Minors (5 seasons)					Minors		8	17	.320	4.82	5.60	128	35	34	0	0	10	241.0	220	150	129	24	124	1	301	27	3	24	1069	1.427	8.2	0.9	4.6	11.2	2.43
College (3 seasons)					College		17	11	.607	4.68	5.01	47	42		1	0	0	221.0	184	123	115	22	118	1	260	40	2	31	980	1.367	7.5	0.9	4.8	10.6	2.20
Other (2 seasons)					Other		0	1	.000	3.60	4.20	22	1	9	0	0	6	30.0	16	14	12	3	17	1	38	1	0	4	122	1.100	4.8	0.9	5.1	11.4	2.24
All Levels (8 Seasons)							27	29	.482	4.60	5.13	225	78	48	1	0	17	522.1	438	298	267	51	271	4	640	70	5	60	2292	1.357	7.5	0.9	4.7	11.0	2.36

AAA (1 season)					Minors		0	3	.000	4.73	5.57	23	1	14	0	0	4	32.1	25	20	17	4	18	1	39	6	1	1	143	1.330	7.0	1.1	5.0	10.9	2.17
AA (3 seasons)					Minors		4	4	.500	3.34	4.01	47	0	14	0	0	5	67.1	45	30	25	8	47	0	97	7	0	5	295	1.366	6.0	1.1	6.3	13.0	2.06
A+ (1 season)					Minors		2	4	.333	5.79	6.08	28	5	6	0	0	1	60.2	58	41	39	6	29	0	73	8	2	10	268	1.434	8.6	0.9	4.3	10.8	2.52
A (2 seasons)					Minors		2	4	.333	6.45	8.26	14	13	0	0	0	0	44.2	56	41	32	2	15	0	43	2	0	4	206	1.590	11.3	0.4	3.0	8.7	2.87
A- (1 season)					Minors		0	2	.000	4.50	4.91	12	12	0	0	0	0	22.0	24	12	11	2	12	0	31	3	0	2	101	1.636	9.8	0.8	4.9	12.7	2.58
Rk (1 season)					Minors		0	0		3.21	3.86	4	4	0	0	0	0	14.0	12	6	5	2	3	0	18	1	0	2	56	1.071	7.7	1.3	1.9	11.6	6.00
Fal (1 season)					Other		0	1	.000	4.80	6.00	9	1	0	0	0	0	15.0	11	10	8	2	8	0	18	1	0	2	64	1.267	6.6	1.2	4.8	10.8	2.25
Smr (1 season)					Other		0	0		2.40	2.40	13	0	9	0	0	6	15.0	5	4	4	1	9	1	20	0	0	2	58	0.933	3.0	0.6	5.4	12.0	2.22