| Season | League | Apps | Min | Goals | Assists | G+A / 90 | Rating |
|---|---|---|---|---|---|---|---|
| 2019 | USL Championship (United States) | 28 | 1927 | 7 | 4 | 0.51 | — |
| 2020 | USL Championship (United States) | 17 | 1494 | 5 | 4 | 0.54 | 7.35 |
| 2021 | USL Championship (United States) | 28 | 2333 | 1 | 5 | 0.23 | 6.98 |
| 2022 | USL Championship (United States) | 36 | 3006 | 4 | 11 | 0.45 | 7.2 |
| 2023 | USL Championship (United States) | 30 | 1333 | 2 | 0 | 0.14 | 6.8 |
| 2024 | USL Championship (United States) | 35 | 2566 | 3 | 5 | 0.28 | 7.24 |
| 2025 | USL Championship (United States) | 30 | 2462 | 4 | 2 | 0.22 | 7.2 |
| 2026 | USL Championship (United States) | 14 | 964 | 0 | 1 | 0.09 | 6.86 |
Domestic league competitions only (SportMonks sub_type='domestic'); national-team, continental and cup competitions are excluded. Classification resolved by league id against the canonical leagues index. G+A/90 computed from minutes actually played.
Figures computed from the GioScore season-stats database · as of 2026-07-27
Player stats against each opponent club
| Team | MP | W | D | L | G | A | ||
|---|---|---|---|---|---|---|---|---|
 Tampa Bay Rowdies | 7 | 3 | 1 | 3 | 0 | 0 | 0 | 0 |
 Hartford Athletic | 7 | 4 | 1 | 2 | 0 | 0 | 2 | 0 |
 Detroit City | 6 | 2 | 3 | 1 | 1 | 2 | 3 | 0 |
 Indy Eleven | 6 | 2 | 2 | 2 | 0 | 0 | 2 | 0 |
 Charleston Battery | 6 | 3 | 1 | 2 | 1 | 0 | 1 | 0 |
 Loudoun United | 5 | 2 | 2 | 1 | 2 | 1 | 0 | 0 |
 Rhode Island | 5 | 4 | 1 | 0 | 2 | 0 | 1 | 0 |
 Louisville City | 4 | 0 | 1 | 3 | 0 | 0 | 1 | 0 |
 Birmingham Legion | 4 | 2 | 1 | 1 | 1 | 1 | 0 | 0 |
 Orange County | 3 | 0 | 2 | 1 | 0 | 0 | 0 | 0 |
 New Mexico United | 3 | 2 | 0 | 1 | 1 | 0 | 0 | 0 |
 Monterey Bay | 3 | 1 | 1 | 1 | 0 | 0 | 0 | 0 |
 Phoenix Rising | 2 | 1 | 1 | 0 | 0 | 0 | 0 | 0 |
 North Carolina FC | 2 | 0 | 2 | 0 | 0 | 0 | 1 | 0 |
 Colorado Springs | 2 | 0 | 1 | 1 | 0 | 0 | 0 | 0 |
 Tulsa Roughnecks | 2 | 0 | 2 | 0 | 0 | 0 | 0 | 0 |
 OKC Energy | 2 | 0 | 1 | 1 | 1 | 2 | 1 | 0 |
 San Antonio | 2 | 0 | 1 | 1 | 0 | 0 | 0 | 0 |
 Las Vegas Lights | 2 | 1 | 0 | 1 | 0 | 0 | 0 | 0 |
 Miami FC II | 2 | 2 | 0 | 0 | 0 | 1 | 1 | 0 |
R. Mertz closed the 2026 USL Championship (United States) with 1 assist, without scoring, over 14 appearances (964 minutes) — 0.09 goal involvements per 90. That season graded out at an average match rating of 6.86.
The record shows 8 league seasons for him (2019–2026) across 2 clubs. At his best he averaged 7.35 in 2020, USL Championship (United States); at his worst, 6.8 in 2023.
