Sharrock, normally the wicketkeeper, continued his hot streak with ball, as he picked up three top order wickets with his medium pacers.
"He bowls his heart out in the nets ... so I said to Chris, 'you can bowl'," said Gerard Hobbs.
Saracens captain Dominic Rayner with 44 off 37 balls looked to be set, before being bowled by Walker, leaving them at 124-6.
Viljeon did not grab his first Wanganui club scalp, but conceded only 20 runs from his eight overs.
It was a hard lesson at the Wanganui Collegiate grounds as St Johns Tech wrapped up a very quick 10 wicket win after laying waste to the schoolboys for 53.
With no Year 13 veteran players and only having a handful of training sessions since coming back after the New Year, Collegiate did have a player of note on the pitch, but the trouble was he was wearing Tech's blue.
Old boy Nick Harding took a five-wicket bag, with Travis Bartels also getting three wickets.
The big-hitting Harding would then need only four overs to overtake the target, smashing 43 not out with four boundaries and four sixes.
