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Trainer Comparison

Statistics by Year:
Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 58 161 2.78 26 12 27 16.15% 40.37% $2,531,210 $15,722 $43,642 0 7
Robertino Diodoro 136 354 2.6 97 53 53 27.4% 57.34% $2,133,779 $6,028 $15,690 1 5

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 89 296 3.33 40 27 39 13.51% 35.81% $5,603,177 $18,930 $62,957 5 7
Robertino Diodoro 192 561 2.92 128 107 74 22.82% 55.08% $4,128,650 $7,359 $21,503 2 9

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 77 265 3.44 38 29 30 14.34% 36.6% $4,372,072 $16,498 $56,780 3 7
Robertino Diodoro 179 438 2.45 110 67 57 25.11% 53.42% $3,730,708 $8,518 $20,842 1 7

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 85 261 3.07 26 29 32 9.96% 33.33% $3,230,122 $12,376 $38,001 3 4
Robertino Diodoro 304 785 2.58 150 141 107 19.11% 50.7% $5,867,506 $7,475 $19,301 1 6

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 82 256 3.12 32 31 27 12.5% 35.16% $2,790,593 $10,901 $34,032 1 2
Robertino Diodoro 339 894 2.64 191 152 104 21.36% 50% $6,800,660 $7,607 $20,061 1 11

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 64 228 3.56 37 32 28 16.23% 42.54% $3,591,929 $15,754 $56,124 3 6
Robertino Diodoro 292 904 3.1 223 178 108 24.67% 56.31% $7,496,024 $8,292 $25,671 3 9

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 65 223 3.43 27 22 22 12.11% 31.84% $1,586,106 $7,113 $24,402 2 3
Robertino Diodoro 311 1110 3.57 242 188 152 21.8% 52.43% $6,011,283 $5,416 $19,329 1 9

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 70 252 3.6 38 27 32 15.08% 38.49% $4,221,733 $16,753 $60,310 6 9
Robertino Diodoro 310 1043 3.36 257 182 183 24.64% 59.64% $5,763,032 $5,525 $18,590 0 7

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 57 247 4.33 38 27 31 15.38% 38.87% $2,476,021 $10,024 $43,439 5 6
Robertino Diodoro 321 1056 3.29 255 180 150 24.15% 55.4% $6,078,667 $5,756 $18,937 2 7

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 64 266 4.16 33 36 42 12.41% 41.73% $2,768,718 $10,409 $43,261 5 9
Robertino Diodoro 306 970 3.17 219 163 126 22.58% 52.37% $5,162,000 $5,322 $16,869 2 7

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 57 248 4.35 36 33 34 14.52% 41.53% $2,238,309 $9,025 $39,269 1 3
Robertino Diodoro 258 933 3.62 242 168 115 25.94% 56.27% $4,642,888 $4,976 $17,996 1 7

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 53 200 3.77 20 25 21 10% 33% $1,078,969 $5,395 $20,358 0 0
Robertino Diodoro 241 813 3.37 190 141 95 23.37% 52.4% $3,198,906 $3,935 $13,273 0 7

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 50 214 4.28 23 38 29 10.75% 42.06% $1,474,259 $6,889 $29,485 2 2
Robertino Diodoro 276 920 3.33 243 149 137 26.41% 57.5% $3,780,862 $4,110 $13,699 1 5

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 65 234 3.6 27 32 29 11.54% 37.61% $1,704,902 $7,286 $26,229 3 5
Robertino Diodoro 175 653 3.73 149 132 87 22.82% 56.36% $2,356,297 $3,608 $13,465 2 8

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 64 260 4.06 36 41 35 13.85% 43.08% $2,354,583 $9,056 $36,790 4 7
Robertino Diodoro 168 619 3.68 106 86 85 17.12% 44.75% $1,542,746 $2,492 $9,183 0 2

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 84 294 3.5 34 40 38 11.56% 38.1% $1,434,029 $4,878 $17,072 0 0
Robertino Diodoro 166 667 4.02 137 117 99 20.54% 52.92% $1,748,505 $2,621 $10,533 0 1

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 82 304 3.71 37 43 36 12.17% 38.16% $2,105,210 $6,925 $25,673 2 4
Robertino Diodoro 152 533 3.51 109 71 79 20.45% 48.59% $1,200,249 $2,252 $7,896 0 7

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 83 309 3.72 43 39 41 13.92% 39.81% $2,266,502 $7,335 $27,307 4 4
Robertino Diodoro 115 401 3.49 61 50 58 15.21% 42.14% $650,377 $1,622 $5,655 0 2

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 81 313 3.86 50 36 40 15.97% 40.26% $2,392,905 $7,645 $29,542 4 7
Robertino Diodoro 98 389 3.97 64 49 41 16.45% 39.59% $653,231 $1,679 $6,666 0 2

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 70 254 3.63 32 43 43 12.6% 46.46% $1,952,114 $7,685 $27,887 2 4
Robertino Diodoro 89 346 3.89 55 60 41 15.9% 45.09% $708,077 $2,046 $7,956 0 4

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 49 171 3.49 29 17 16 16.96% 36.26% $986,944 $5,772 $20,142 0 0
Robertino Diodoro 67 253 3.78 27 30 21 10.67% 30.83% $307,573 $1,216 $4,591 0 0

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 47 166 3.53 22 23 26 13.25% 42.77% $1,133,117 $6,826 $24,109 3 3
Robertino Diodoro 53 235 4.43 29 38 20 12.34% 37.02% $288,205 $1,226 $5,438 0 0

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 51 189 3.71 24 25 28 12.7% 40.74% $1,270,678 $6,723 $24,915 0 6
Robertino Diodoro 47 223 4.74 31 28 19 13.9% 34.98% $355,973 $1,596 $7,574 0 1

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 63 259 4.11 34 47 35 13.13% 44.79% $1,961,444 $7,573 $31,134 1 5
Robertino Diodoro 66 301 4.56 30 45 39 9.97% 37.87% $382,529 $1,271 $5,796 0 1

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 58 269 4.64 36 43 36 13.38% 42.75% $1,775,316 $6,600 $30,609 0 6
Robertino Diodoro 52 244 4.69 29 42 34 11.89% 43.03% $335,720 $1,376 $6,456 0 0

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 69 289 4.19 47 43 37 16.26% 43.94% $2,421,943 $8,380 $35,101 2 6
Robertino Diodoro 44 227 5.16 33 25 21 14.54% 34.8% $248,130 $1,093 $5,639 0 0

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 68 363 5.34 47 61 45 12.95% 42.15% $2,262,516 $6,233 $33,272 0 8
Robertino Diodoro 38 182 4.79 28 25 23 15.38% 41.76% $149,680 $822 $3,939 0 0

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 71 322 4.54 60 47 29 18.63% 42.24% $2,771,678 $8,608 $39,038 1 7
Robertino Diodoro 27 149 5.52 14 21 14 9.4% 32.89% $75,393 $506 $2,792 0 0

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 61 268 4.39 42 44 34 15.67% 44.78% $1,968,309 $7,344 $32,267 1 5
Robertino Diodoro 35 161 4.6 13 20 22 8.07% 34.16% $91,277 $567 $2,608 0 0

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 54 270 5 51 35 33 18.89% 44.07% $2,532,526 $9,380 $46,899 5 7
Robertino Diodoro 18 76 4.22 9 8 9 11.84% 34.21% $47,126 $620 $2,618 0 0

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 53 275 5.19 40 31 36 14.55% 38.91% $1,861,011 $6,767 $35,113 2 4
Robertino Diodoro 9 43 4.78 5 7 4 11.63% 37.21% $27,627 $642 $3,070 0 0

Name Starters Starts Starts/
Starter 		1st 2nd 3rd Win % % 1st, 2nd or 3rd Earned Avg Earnings per Start Avg Earnings Per Starter Graded Stakes Win All Black-Type Win
2025 National Trainer Avg. 4 13.53% 40.55% $5,513 $22,031
George R. Arnold II 52 230 4.42 26 35 33 11.3% 40.87% $1,043,833 $4,538 $20,074 2 2
Robertino Diodoro 4 17 4.25 3 3 3 17.65% 52.94% $14,304 $841 $3,576 0 0