Rudolph - 84.
Yorkshire moved to second place in Division Two of the NatWest Pro40 League when they overcame Glamorgan Dragons by 49 runs at Scarborough under the Duckworth-Lewis system.
Chasing a target of 231, the deteriorating light became too poor to continue immediately after former Yorkshire player Alex Wharf had been dismissed by Darren Gough, to leave the Dragons on 135 for seven in the 30th over.
Robert Croft got Glamorgan's reply off to a positive start and he had contributed 25 to an opening stand of 35 inside eight overs with David Hemp when he drove Rana Naved-ul-Hasan to Gough at mid-on.
With the weather closing in, Glamorgan were ahead of the required rate until Mike Powell steered Rana to Richard Pyrah at backward point and the accurate Deon Kruis bowled Tom Maynard to return the tidy figures of one for 26 from eight overs.
Glamorgan slumped to 71 for four in 16 overs as Gough bowled Jamie Dalrymple's and rain was starting to fall when Richard Pyrah bowled David Hemp.
Although the rain stopped, bad light made it impossible to complete the match.
The bulk of Yorkshire's runs came from a 164-run partnership for the third wicket between Jacques Rudolph and Anthony McGrath.
After a slow start to his innings, South African Rudolph dashed on to 84 off 93 balls with 11 fours and a six while McGrath smashed 73 from 96 deliveries with four fours and three sixes.
The stand was just 12 runs short of Yorkshire's record for the third wicket in the competition, Richard Blakey and Sachin Tendulkar having put on 176 against Lancashire at Headingley in 1992.
Winning the toss under grey skies, Yorkshire soon lost Andrew Gale who fell lbw to 18-year-old James Harris, but there was early entertainment for the 4,000 crowd from Rana.
He lashed four quick fours as well as cross-batting former Yorkshire paceman Jason Gillespie for a low six which cleared the ground at the Trafalgar Square end.
All but two of Rana's 24 runs came from boundaries before a curving delivery from Gillespie was well taken low down at second slip by Powell.
Rudolph had begun so cautiously that he managed only six runs off his first 28 deliveries before off-driving Wharf for his first boundary and adding another four with a cover drive off the next ball.
McGrath drove left-armer Dean Cosker for two big straight sixes, and in a later over from Croft each batsman hit the off-spinner for six as the stand continued to mount.
Rudolph was denied a century when he dragged a ball from Dalrymple into his stumps, the batsman delaying his exit for a while because he felt there was a possibility the ball had cannoned off wicketkeeper Wallace's pads.
McGrath departed in the next over when he hit a full toss from Gillespie to Powell at mid-on to give the Australian his 250th List A wicket.