Kobe Bryant has the most career games by a player younger than 19, with 71 games.

Interpreted as:

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

	NAME	GP	MPG	PPG	RPG	APG	SPG	BPG	FGM	FGA	FG%	3PM	3PA	3P%	FTM	FTA	FT%	TS%	OREB	DREB	TPG	MIN	PTS	REB	AST	STL	BLK	TOV	PF	+/-
1	Kobe Bryant K. Bryant	71	15.5	7.6	1.9	1.3	0.7	0.3	2.5	5.9	41.7	0.7	1.9	37.5	1.9	2.3	81.9	54.4	0.7	1.2	1.6	1,103	539	132	91	49	23	112	102	+60
2	Tracy McGrady T. McGrady	64	18.4	7.0	4.2	1.5	0.8	1.0	2.8	6.2	45.0	0.2	0.6	34.1	1.2	1.7	71.2	50.5	1.6	2.6	1.0	1,179	451	269	98	49	61	66	86	-229
3	Bill Willoughby B. Willoughby	62		4.7					1.8						1.1	1.6	66.0						292
4	Andrew Bynum A. Bynum	46	7.4	1.6	1.7	0.2	0.1	0.5	0.7	1.8	40.2	0.0	0.0		0.2	0.6	29.6	39.4	0.7	1.0	0.4	338	74	80	9	4	22	17	56	-47
5	Jermaine O'Neal J. O'Neal	45	10.2	4.1	2.8	0.2	0.0	0.6	1.5	3.4	45.1	0.0	0.0	0.0	1.0	1.7	60.3	49.4	0.9	1.9	0.6	458	185	124	8	2	26	27	46	+26
6	Darko Milicic D. Milicic	34	4.7	1.4	1.3	0.2	0.2	0.4	0.5	1.9	26.2	0.0	0.0	0.0	0.4	0.7	58.3	31.8	0.3	0.9	0.4	159	48	43	7	7	15	13	33	-45
7	LeBron James L. James	31	40.2	20.2	5.9	6.1	1.6	0.7	7.6	17.9	42.6	1.0	3.3	31.1	3.8	5.0	77.3	50.1	1.5	4.5	3.9	1,247	625	184	188	49	23	121	56	-67
8	Yaroslav Korolev Y. Korolev	24	5.3	1.1	0.5	0.4	0.1	0.0	0.4	1.3	30.0	0.1	0.3	28.6	0.3	0.4	70.0	39.2	0.2	0.3	0.3	127	27	13	9	3	0	6	11	-8
9	Cooper Flagg C. Flagg	22	33.8	17.3	6.6	3.3	1.4	0.6	6.7	14.1	47.6	0.9	3.5	25.6	2.9	3.6	80.0	54.9	1.2	5.4	2.2	743	380	145	73	30	14	48	52	-153
10	Andris Biedrins A. Biedrins	20	11.9	3.7	3.2	0.3	0.5	0.8	1.6	2.6	59.6	0.0	0.1	0.0	0.6	1.3	42.3	57.5	1.2	2.0	0.4	237	73	63	6	9	15	7	49	+4
11	Darryl Dawkins D. Dawkins	19		1.9	1.4	0.2			0.9	1.8	50.0				0.1	0.5	22.2	47.4					36	26	3				18
12	Stan Brown S. Brown	19		2.6					1.0						0.6								50
13	Joe Graboski J. Graboski	18		3.7					1.5						0.7	1.4	48.0						66
14	CJ Miles	17	7.9	2.4	1.5	0.5	0.2	0.0	0.8	2.9	28.6	0.2	0.8	21.4	0.6	0.8	76.9	37.5	0.6	0.8	0.4	134	41	25	9	4	0	6	15	+16
15	Dwight Howard D. Howard	17	32.0	10.5	10.4	1.6	1.0	1.9	3.8	6.9	54.7	0.0	0.0		3.0	5.1	58.6	57.6	3.8	6.6	2.2	544	179	177	27	17	32	38	40	+19
16	Jalen Duren J. Duren	13	21.4	6.3	7.4	0.3	0.3	1.2	2.7	4.8	55.6	0.0	0.1	0.0	0.9	2.4	38.7	53.5	2.9	4.5	1.1	279	82	96	4	4	15	14	27	-69
17	Giannis Antetokounmpo G. Antetokounmpo	13	16.2	5.2	3.2	0.9	0.5	0.7	2.1	4.1	50.9	0.5	1.2	40.0	0.6	1.2	50.0	56.6	0.7	2.5	1.0	210	68	42	12	7	9	13	23	+3
18	Josh Smith J. Smith	13	12.7	5.1	2.6	0.8	0.3	0.7	1.9	3.9	49.0	0.0	0.2	0.0	1.2	1.9	64.0	53.2	1.0	1.6	1.2	165	66	34	11	4	9	16	18	-8
19	Eddy Curry E. Curry	13	12.4	4.4	2.2	0.3	0.2	0.8	1.5	3.6	40.4	0.0	0.0		1.5	2.4	61.3	47.0	0.6	1.6	0.9	161	57	29	4	2	11	12	23	-44
20	Dragan Bender D. Bender	9	9.4	3.3	1.0	0.4	0.2	0.3	1.3	3.1	42.9	0.7	1.7	40.0	0.0	0.0		53.6	0.3	0.7	0.3	85	30	9	4	2	3	3	12	+16
21	Martell Webster M. Webster	9	9.2	4.0	0.7	0.1	0.1	0.0	1.6	3.6	43.8	0.9	2.0	44.4	0.0	0.0		56.3	0.1	0.6	1.0	83	36	6	1	1	0	9	8	-29
22	Jonathan Bender J. Bender	9	4.4	2.2	0.8	0.0	0.0	0.3	0.9	2.3	38.1	0.2	0.6	40.0	0.2	0.4	50.0	43.9	0.0	0.8	0.4	40	20	7	0	0	3	4	5	-5
23	Joshua Primo J. Primo	8	7.4	2.0	0.8	0.5	0.4	0.5	0.8	1.4	54.5	0.5	1.0	50.0	0.0	0.0		72.7	0.1	0.6	0.0	59	16	6	4	3	4	0	4	+7
24	Joan Beringer J. Beringer	7	4.1	1.7	1.1	0.0	0.1	0.1	0.9	1.0	85.7	0.0	0.0		0.0	0.1	0.0	80.6	0.1	1.0	0.3	29	12	8	0	1	1	2	7	+6
25	Robert Swift R. Swift	7	3.9	0.4	0.0	0.3	0.0	0.1	0.1	0.4	33.3	0.0	0.0		0.1	0.3	50.0	38.7	0.0	0.0	0.0	27	3	0	2	0	1	0	5	-31