EVEN Yerong Creek trainer Christopher Bootsma didn't believe Tilly Rockin' could handle the huge step up in class.
But the four-year-old bitch produced a welcome surprise to win the Interior Constructions Stakes (320m) by a narrow margin at Wagga on Friday.
Stepping up from grade five to free for all class, Tilly Rockin' took advantage of box one to just hold off Bruce Williams dog Myrniong Jake (box six) in a thrilling photo finish.
"It was only a head in it,it was a good result," Bootsma said.
"Coming up from grade five I didn't think she would win today, but the box helped immensely."
Trainer Gregory Berry had a strong day with Atlantic Jewel ($1.60) taking out the Ladbrokes Cash in Final over 525 metres, while Space Alert ($2.10) won the Graeme Hull Smash Repairs Stakes.