Worcester led 9-3 at the break thanks to Walker's accurate kicking show as they were roared on by a passionate home support.
But a second half fight-back from the table toppers saw Walker show his nerve and skill to slot a late penalty to not only earn a share of the points but also spoil the visitors previously unblemished league record.
"We ended up 12-12 and I felt we could have got the spoils again," said Ruddock. "Certainly at 9-3 at half-time I felt we were going to press on and win the game.
"If we played as accurately in the second half as we did in the first half that might have been the case.
"Unfortunately we weren't, particularly in the first 20 minutes of the second half. We allowed Saracens to put us under pressure and they kicked into the corners and put us under pressure at the breakdown behind our forward pack.
" They got a few penalties to nudge ahead so it was a great effort to come back against Saracens, not many sides are doing that, and get a draw.
"It was a great kick from Willie Walker, it was great temperament from him to nail it from out wide. It wasn't an easy kick at all so full marks to him.
"I felt it was an energised and passionate display from us, lots of pride, heart and skill," he added.
"We tried to play some rugby as well and probably in that 20 minute period in the second half we over played a little bit at times and put ourselves under pressure.
"But I don't want to take all that away from my team either, we have got to be prepared to push the boundaries back at times and try and play as well."
Ruddock was also pleased by a second successive league shutout and insisted he was not overly concerned by a lack of tries from his men.
He said: "The lack of tries is not worrying me - as long as we keep them out the other end. We haven't been conceding which is vital.
"The lack of tries is more of a worry for the law makers and it is possibly something that needs to be looked at.
"It's very difficult to play off slow ball, difficult to play when the first defender has got his hands in the ruck, difficult to get the ball wide.
"That has led to a reduction in tries all round, it is not just something I will be focusing on with my team. Everyone needs to be aware of it and hence the penalty goal is king at the moment."
Saracens looked to try take all the points on offer in a frantic finale, however Warriors held firm and a stunning scrum against the head in the dying minutes proved crucial as Worcester held firm.
"It was fantastic to get one against the head. Tony Windo is our Scrum Coach and he does a great job for us, he will be pleased with that," added Ruddock.
"We were very competitive and we're tough to beat. We know we are going to give teams a hard game.
"If I am honest, as pleased as I am that we have picked up another two points, I'm disappointed we haven't nailed this one because at 9-3 at half-time I thought we were on our way to a big win against the top team in England at the moment. But I suppose that is why they are top - they are hard to beat."