Younger than 30: 6 of 8 2003 champion Marlins.

The Marlins finished second but won the 2003 tournament when they beat the Yankees in the finals.  Six of the eight Marlin regular fielders were younger than 30 years old, the oldest only 31.

http://www.baseball-reference.com/teams/FLA/2003.shtml

Rk	Pos	Name	Age	G	PA	AB	R	H	2B	3B	HR	RBI	SB	CS	BB	SO	BA	OBP	SLG	OPS	OPS+	TB	GDP	HBP	SH	SF	IBB
1	C	Ivan Rodriguez	31	144	578	511	90	152	36	3	16	85	10	6	55	92	.297	.369	.474	.843	120	242	18	6	1	5	6
2	1B	Derrek Lee	27	155	643	539	91	146	31	2	31	92	21	8	88	131	.271	.379	.508	.888	131	274	9	10	0	6	7
3	2B	Luis Castillo#	27	152	676	595	99	187	19	6	6	39	21	19	63	60	.314	.381	.397	.778	106	236	7	2	15	1	0
4	SS	Alex Gonzalez	26	150	582	528	52	135	33	6	18	77	0	4	33	106	.256	.313	.443	.756	96	234	8	13	3	5	13
5	3B	Mike Lowell	29	130	557	492	76	136	27	1	32	105	3	1	56	78	.276	.350	.530	.881	128	261	14	3	0	6	6
6	LF	Todd Hollandsworth*	30	93	254	228	32	58	23	3	3	20	2	3	22	55	.254	.317	.421	.739	93	96	2	0	2	2	4
7	CF	Juan Pierre*	25	162	747	668	100	204	28	7	1	41	65	20	55	35	.305	.361	.373	.734	94	249	9	5	15	3	1
8	RF	Juan Encarnacion	27	156	653	601	80	162	37	6	19	94	19	8	37	82	.270	.313	.446	.759	97	268	17	4	5	6	0
Rk	Pos	Name	Age	G	PA	AB	R	H	2B	3B	HR	RBI	SB	CS	BB	SO	BA	OBP	SLG	OPS	OPS+	TB	GDP	HBP	SH	SF	IBB
9	UT	Miguel Cabrera	20	87	346	314	39	84	21	3	12	62	0	2	25	84	.268	.325	.468	.793	106	147	12	2	4	1	3

Notice the 20 year old utility player at the bottom and not counted among the eight regulars.



Yankees model: old fielders on 2001 Arizona champion?  Tuesday, November 18, 2014

​Nine "regular" fielders at least 30 years old.
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