His strongest working relationship is with trainer Jim Goldie, and the numbers tell you everything: 35 wins from 232 rides together, which works out at roughly 1 in every 7 — well above the average for any jockey-trainer partnership. That kind of consistency doesn't happen by accident. It speaks to trust, communication, and a jockey who clearly understands what a particular yard needs from him.
Mulrennan also has a notable affinity for Ayr, one of Scotland's most important tracks, where he has ridden 15 winners from 73 races. That's just over 1 in every 5, a win rate that any rider would be delighted with at their favourite course. And when the weather turns and the ground gets wet and heavy, he tends to thrive — picking up 3 wins from just 13 races on that kind of surface, a remarkable 23%, or nearly 1 in every 4.
This season has been slightly quieter by his own standards. He has ridden 78 winners from 798 races — roughly 1 in every 10 — compared to a win rate of around 1 in every 7 last year. That dip is worth noting, though it is worth keeping in perspective: 78 winners in a single season is still a substantial haul, and his Ascot success this June suggests the biggest occasions are still bringing out his best. Whether this season represents a temporary dip or something more significant is the interesting question heading into the second half of the year.
| Course | Races | Wins | Win rate |
|---|---|---|---|
| Newcastle | 220 | 18 | 8.2% |
| Southwell | 81 | 7 | 8.6% |
| Ayr | 73 | 15 | 20.5% |
| Musselburgh | 70 | 9 | 12.9% |
| Hamilton Park | 65 | 11 | 16.9% |
| Thirsk | 45 | 5 | 11.1% |
| Haydock Park | 38 | 4 | 10.5% |
| York | 28 | 2 | 7.1% |
| Carlisle | 26 | 1 | 3.8% |
| Beverley | 25 | 1 | 4% |
| Catterick Bridge | 19 | 2 | 10.5% |
| Wolverhampton | 17 | 0 | 0% |
| Doncaster | 17 | 0 | 0% |
| Redcar | 15 | 1 | 6.7% |
| Pontefract | 13 | 0 | 0% |
| Nottingham | 12 | 0 | 0% |
| Chester | 10 | 0 | 0% |
| Ripon | 9 | 1 | 11.1% |
| Ascot | 6 | 1 | 16.7% |
| Goodwood | 4 | 0 | 0% |
| Lingfield Park | 2 | 0 | 0% |
| Leicester | 2 | 0 | 0% |
| Newmarket | 1 | 0 | 0% |