Mel Ott has the most career games by a player younger than 19, with 117 games.

Interpreted as:

most regular-season games before turning 19 years old by a player

	NAME	G	AB	R	H	2B	3B	HR	RBI	BB	HBP	SO	SB	CS	PA	TB	XBH	SH	SF	IBB	GIDP	AVG	OBP	SLG	OPS
1	Mel Ott M. Ott	117	223	30	69	9	3	1	23	14	0	18	3		241	87	13	4				.309	.350	.390	.740
2	Robin Yount R. Yount	107	344	48	86	14	5	3	26	12	1	46	7	7	364	119	22	5	2	0	4	.250	.276	.346	.622
3	Tommy Brown T. Brown	103	342	30	72	7	4	2	27	14	0	34	3		364	93	13	8			6	.211	.242	.272	.514
4	Ed Kranepool E. Kranepool	89	279	22	58	13	2	2	14	18	0	51	4	3	300	81	17	1	2	0	10	.208	.254	.290	.545
5	Phil Cavarretta P. Cavarretta	82	327	48	99	18	9	5	52	20	1	33	3		351	150	32	3				.303	.345	.459	.804
6	Lew Malone L. Malone	76	201	17	41	4	4	1		22	1	40	7		228	56	9	4				.204	.286	.279	.564
7	Wayne Causey W. Causey	68	175	14	34	2	1	1	9	17	1	25	0	2	196	41	4	3	0	1	2	.194	.269	.234	.504
8	Frank O'Rourke F. O'Rourke	61	196	11	24	3	1	0	15	11	2	50	1		216	29	4	7				.122	.177	.148	.325
9	Merito Acosta M. Acosta	60	111	17	28	3	3	0		19	1	23	6		133	37	6	2				.252	.366	.333	.700
10	Willie Crawford W. Crawford	53	39	11	7	1	0	0	0	3	0	15	1	1	42	8	1	0	0	0	0	.179	.238	.205	.443
11	Freddie Lindstrom F. Lindstrom	53	79	19	20	3	1	0	4	6	1	10	3		88	25	4	2				.253	.314	.316	.630
12	Clete Boyer C. Boyer	47	79	3	19	1	0	0	6	4	0	20	0	0	83	20	1	0	0	0	3	.241	.277	.253	.530
13	Bob Feller B. Feller	40	75	3	12	1	1	0	9	3	0	27	0		79	15	2	1				.160	.192	.200	.392
14	Ed Kirkpatrick E. Kirkpatrick	37	83	4	15	5	0	2	7	6	1	21	1	0	91	26	7	0	1	0	1	.181	.242	.313	.555
15	Skip Lockwood S. Lockwood	36	30	3	3	0	0	0	0	5	1	10	0	0	36	3	0	0	0	0	0	.100	.250	.100	.350
16	Jimmie Foxx J. Foxx	36	41	10	16	3	1	0	6	1	0	7	1		44	21	4	2				.390	.405	.512	.917
17	Granny Hamner G. Hamner	35	118	9	26	3	0	0	11	4	0	10	0		123	29	3	1			2	.220	.246	.246	.492
18	Tony La Russa T. La Russa	34	44	4	11	1	1	0	1	7	0	12	0	0	53	14	2	1	1	0	0	.250	.346	.318	.664
19	Dick Schofield D. Schofield	33	39	9	7	0	0	2	4	2	0	11	0	1	41	13	2	0			0	.179	.220	.333	.553
20	Danny Murphy D. Murphy	31	75	7	9	2	0	1	6	4	1	13	0	0	81	14	3	1	0	0	2	.120	.175	.187	.362
21	Cal McLish C. McLish	31	32	6	7	1	0	0	1	0	0	12	0		33	8	1	1			1	.219	.219	.250	.469
22	Al Kaline A. Kaline	30	28	9	7	0	0	1	2	1	1	5	1	0	30	10	1	0			1	.250	.300	.357	.657
23	Billy Consolo B. Consolo	30	39	4	9	1	1	1	6	0	0	11	1	2	39	15	3	0			0	.231	.231	.385	.615
24	Jim Brillheart J. Brillheart	30	34	0	2	0	0	0	1	0	1	14	0		36	2	0	1				.059	.086	.059	.145
25	Bobby Henrich B. Henrich	29	10	8	2	0	0	0	1	1	0	4	0	0	12	2	0	0	1	0	0	.200	.250	.200	.450