Drahm, who will join Japanese side Kubota Spears at the end of the season, was only recalled from a short-term loan spell at League One Launceston last weekend after an injury ruled out fly-half Loki Crichton.
But Drahm outshone Sale's England hopeful Charlie Hodgson, landing four penalties, as Worcester recorded only their second home win of the season to put some much-needed distance between themselves and bottom club Leeds Carnegie.
"Shane Drahm was fantastic for us - he deserves a lot of credit," said Ruddock. "He kicked everything that moved and kept us ahead - he was the difference.
"I'm very pleased - I said it would take a big effort and we certainly produced that.
"We talked about playing with the spirit of underdogs but the performance of champions and our try was a real champion's effort.
"It was well worked, well executed and in the end proved to be enough.
"Our discipline was much better and that ultimately gave us the result. It was a very good Sale team who had to chase the game and we forced them into errors.
"We didn't give away as many penalties as we had done previously and that was a massive improvement for us."
Sale, who had won their three previous Guinness Premiership games, knew a second league win of the season against Worcester would see them leapfrog Bath and Leicester to go second in the table.
But it was not to be as a strong Sale side, including England stars Andrew Sheridan, Richard Wigglesworth and Mark Cueto, failed to sparkle without their injured talisman - Kiwi Luke McAlister.
The difference between the two sides proved to be a first-half score from Kai Horstmann and the impeccable kicking of Drahm as Sale missed a crucial opportunity to climb the table.
"I think the Premiership is a tough competition," said Sale director of rugby Philippe Saint Andre, who was far from impressed with his side's lacklustre showing.
"There are no easy games in this competition - the conditions were very difficult and Worcester were very clinical while we made a lot of mistakes."