"It was wet and the track was cold. In fact, the meeting was supposed to run on Sunday, but was postponed until Monday because of the rain.
"And even on Monday the track was cold and every time he stood on it [accelerator] the wheels would spin, so Adrian did a fantastic job pedalling it to catch his rivals - he won it on sheer driving skills," Rivers snr said yesterday.
At Taupo, Rivers covered the quarter mile in 6.9 seconds clocking speeds of 198km/h in the cold conditions, slightly down on the New Zealand record he set in Masterton earlier in the season clocking a speed of 200 miles per hour (320km/h).
"He covered the quarter mile in Masterton in 6.7s shaving .5 of a second off the national record and he went through unbeaten in Nelson a couple of weeks ago - he's had a fantastic season," Rivers snr said.
Until Monday the best Rivers had done was achieve No2 in the modified division, while his 24-year-old sister Nicole has two No2 stickers - in the junior and modified divisions. She did not compete this year.
"I'm really proud of them both and especially Adrian getting two No1s," he said. "In all my years of racing I've never had a No1, but at least I can say I helped build and set up the motor for this season."