Team fielding -- 2021 Seattle Mariners
Regular season -- as of 10/3/2021
| Primary |
| Pos | S | Name | G | GS | INN | PO | A | E | DP | TC | PCT | PB | SB | CS | SB% | PK |
| p | | Anthony Bender | 80 | 0 | 100.7 | 12 | 14 | 1 | 1 | 27 | .963 | | 8 | 8 | .500 | 0 |
| | | Shane McClanahan | 34 | 28 | 154.7 | 10 | 12 | 2 | 2 | 24 | .917 | | 16 | 1 | .941 | 1 |
| | | Luis H. Garcia | 31 | 25 | 129.7 | 10 | 9 | 2 | 0 | 21 | .905 | | 11 | 5 | .688 | 1 |
| | | Josiah Gray | 28 | 25 | 134.3 | 8 | 10 | 3 | 2 | 21 | .857 | | 10 | 8 | .556 | 0 |
| | | Huascar Ynoa | 27 | 10 | 73.3 | 7 | 9 | 0 | 1 | 16 | 1.000 | | 3 | 4 | .429 | 1 |
| | | Sam Long | 40 | 0 | 51.3 | 4 | 11 | 0 | 1 | 15 | 1.000 | | 3 | 0 | 1.000 | 0 |
| | | Carlos E. Hernandez | 22 | 11 | 73.0 | 6 | 6 | 1 | 0 | 13 | .923 | | 8 | 0 | 1.000 | 1 |
| | f | Brailyn Marquez | 21 | 10 | 68.0 | 5 | 5 | 1 | 0 | 11 | .909 | | 2 | 1 | .667 | 1 |
| | f | Tyler Glasnow | 14 | 14 | 82.3 | 3 | 5 | 2 | 0 | 10 | .800 | | 9 | 4 | .692 | 0 |
| | f | Jhoan Duran | 28 | 8 | 61.3 | 5 | 4 | 0 | 0 | 9 | 1.000 | | 6 | 3 | .667 | 0 |
| | | Emmanuel Clase | 75 | 0 | 84.7 | 4 | 4 | 0 | 0 | 8 | 1.000 | | 2 | 1 | .667 | 1 |
| | | Bryan Abreu | 8 | 8 | 40.3 | 2 | 5 | 0 | 1 | 7 | 1.000 | | 3 | 2 | .600 | 1 |
| | | Adbert Alzolay | 40 | 8 | 71.3 | 2 | 5 | 0 | 0 | 7 | 1.000 | | 5 | 9 | .357 | 1 |
| | | Jose Quijada | 9 | 0 | 9.3 | 0 | 0 | 0 | 0 | 0 | .000 | | 1 | 1 | .500 | 0 |
| | | Other | 170 | 15 | 269.7 | 14 | 19 | 2 | 0 | 35 | .943 | | 18 | 9 | .667 | 2 |
| | | Total | 627 | 162 | 1404.0 | 92 | 118 | 14 | 8 | 224 | .938 | | 105 | 56 | .652 | 10 |
| | | | | | | | | | | | | | | | | |
| c | | Adley Rutschman | 155 | 153 | 1324.0 | 1337 | 89 | 13 | 0 | 1439 | .991 | 34 | 99 | 51 | .660 | 2 |
| | | Other | 15 | 9 | 80.0 | 75 | 8 | 0 | 0 | 83 | 1.000 | 9 | 6 | 5 | .545 | 0 |
| | | Total | 170 | 162 | 1404.0 | 1412 | 97 | 13 | 0 | 1522 | .991 | 43 | 105 | 56 | .652 | 2 |
| | | | | | | | | | | | | | | | | |
| 1b | | Nick Pratto | 94 | 89 | 782.7 | 738 | 71 | 6 | 47 | 815 | .993 | | | | | |
| | | Taylor Trammell | 1 | 0 | 1.0 | 1 | 0 | 0 | 0 | 1 | 1.000 | | | | | |
| | | Other | 73 | 73 | 620.3 | 551 | 43 | 5 | 45 | 599 | .992 | | | | | |
| | | Total | 168 | 162 | 1404.0 | 1290 | 114 | 11 | 92 | 1415 | .992 | | | | | |
| | | | | | | | | | | | | | | | | |
| 2b | | Vidal Brujan | 162 | 162 | 1404.0 | 275 | 481 | 23 | 78 | 779 | .970 | | | | | |
| | | Total | 162 | 162 | 1404.0 | 275 | 481 | 23 | 78 | 779 | .970 | | | | | |
| | | | | | | | | | | | | | | | | |
| 3b | | Oneil Cruz | 131 | 131 | 1100.0 | 69 | 225 | 34 | 15 | 328 | .896 | | | | | |
| | | Rodolfo Castro | 26 | 18 | 169.0 | 7 | 23 | 1 | 2 | 31 | .968 | | | | | |
| | | Luis Rengifo | 8 | 8 | 68.0 | 5 | 12 | 3 | 3 | 20 | .850 | | | | | |
| | | Samad Taylor | 7 | 5 | 42.0 | 4 | 7 | 2 | 0 | 13 | .846 | | | | | |
| | f | Christopher Morel | 17 | 0 | 25.0 | 0 | 7 | 1 | 0 | 8 | .875 | | | | | |
| | | Total | 189 | 162 | 1404.0 | 85 | 274 | 41 | 20 | 400 | .897 | | | | | |
| | | | | | | | | | | | | | | | | |
| ss | | Geraldo Perdomo | 149 | 149 | 1294.0 | 163 | 455 | 21 | 64 | 639 | .967 | | | | | |
| | | Luis Garcia | 13 | 13 | 109.0 | 8 | 31 | 3 | 6 | 42 | .929 | | | | | |
| | f | Christopher Morel | 1 | 0 | 1.0 | 1 | 0 | 0 | 0 | 1 | 1.000 | | | | | |
| | | Total | 163 | 162 | 1404.0 | 172 | 486 | 24 | 70 | 682 | .965 | | | | | |
| | | | | | | | | | | | | | | | | |
| lf | | Jesus Sanchez | 57 | 57 | 489.0 | 97 | 2 | 3 | 0 | 102 | .971 | | | | | |
| | | Luis Rengifo | 26 | 26 | 230.3 | 34 | 1 | 0 | 0 | 35 | 1.000 | | | | | |
| | | Edward Olivares | 15 | 15 | 128.0 | 25 | 1 | 1 | 0 | 27 | .963 | | | | | |
| | | Taylor Trammell | 12 | 10 | 76.7 | 19 | 0 | 1 | 0 | 20 | .950 | | | | | |
| | | Rodolfo Castro | 2 | 0 | 4.0 | 2 | 0 | 0 | 0 | 2 | 1.000 | | | | | |
| | | Oswaldo Cabrera | 1 | 0 | 7.0 | 0 | 0 | 0 | 0 | 0 | .000 | | | | | |
| | | Other | 59 | 54 | 469.0 | 103 | 0 | 1 | 0 | 104 | .990 | | | | | |
| | | Total | 172 | 162 | 1404.0 | 280 | 4 | 6 | 0 | 290 | .979 | | | | | |
| | | | | | | | | | | | | | | | | |
| cf | | Taylor Trammell | 97 | 91 | 762.0 | 178 | 4 | 2 | 1 | 184 | .989 | | | | | |
| | | Jake McCarthy | 36 | 35 | 302.0 | 80 | 0 | 1 | 0 | 81 | .988 | | | | | |
| | | Jesus Sanchez | 26 | 26 | 226.3 | 50 | 2 | 0 | 0 | 52 | 1.000 | | | | | |
| | | Edward Olivares | 1 | 0 | 1.0 | 0 | 0 | 0 | 0 | 0 | .000 | | | | | |
| | | Other | 34 | 10 | 112.7 | 38 | 1 | 1 | 0 | 40 | .975 | | | | | |
| | | Total | 194 | 162 | 1404.0 | 346 | 7 | 4 | 1 | 357 | .989 | | | | | |
| | | | | | | | | | | | | | | | | |
| rf | | Edward Olivares | 85 | 85 | 738.3 | 135 | 7 | 9 | 0 | 151 | .940 | | | | | |
| | | Jesus Sanchez | 47 | 45 | 379.7 | 75 | 7 | 0 | 1 | 82 | 1.000 | | | | | |
| | | Taylor Trammell | 4 | 0 | 6.3 | 2 | 0 | 0 | 0 | 2 | 1.000 | | | | | |
| | | Luis Rengifo | 1 | 0 | 1.0 | 0 | 0 | 0 | 0 | 0 | .000 | | | | | |
| | | Jake McCarthy | 1 | 0 | 2.0 | 0 | 0 | 0 | 0 | 0 | .000 | | | | | |
| | | Other | 33 | 32 | 276.7 | 48 | 1 | 1 | 0 | 50 | .980 | | | | | |
| | | Total | 171 | 162 | 1404.0 | 260 | 15 | 10 | 1 | 285 | .965 | | | | | |
| | | | | | | | | | | | | | | | | |
| | | Total | 162 | 162 | 1404.0 | 4212 | 1596 | 146 | 95 | 5954 | .975 | 43 | | | | |
