WESTBURY has all but locked in a home final after completing a thumping outright win over Riverside.
Locked in an arm wrestle at the end of day one, the Shamrocks lost their eighth wicket, Corey Briggs, four runs into the eight-run chase but did little else wrong from there.
Claiming first innings points 10 balls later, the Shamrocks finished on 172 all out after birthday boy Alex Kerrison (37* off 87) and Nick Spencer (11 off 62) put on 46 for the last wicket - the game's equal-highest stand.
Riverside was rolled for 68 inside 35 overs before Shamrocks coach and man of the match Matt Battle picked off each of the remaining 11 runs.
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Shamrocks captain Dan Murfet emphasised the importance of claiming first-innings points early in the day.
"Thankfully we got past that hurdle and that really set up the day for us - if we had have been on the losing side of that the rest of the day becomes completely different," he said.
"Alex and Nick were able to get a partnership together and show the top order how to bat a little bit ... they put us in a position where they felt as if they had nothing to lose.
"Our bowling effort was backed up from last week - we know [the bowlers are] very dangerous and they were absolutely clinical today.
"It was one of those days when everything goes your way and those days don't happen too often."
Kerrison (3-14 off nine), Joel Lloyd (3-22 off eight) and Spencer (2-11 off 10) were the pick of the bowlers as Sam Lockett (18) top-scored for a Blues side that missed skipper Tom Garwood.
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LAUNCESTON's winning run shows no sign of stopping after a convincing first-innings victory over South Launceston.
Resuming with the Knights on 4-67 in pursuit of 250, the Lions were made to wait 90 minutes for the first wicket as Tom Waller (41) and Doug Ryan (35) knuckled down.
A 50-run stand ended when Waller nicked off to Rowan Smith and wickets followed regularly thereafter as a run-a-ball 56 from captain Sean Harris helped the Knights to 185.
Lions paceman Daniel Smith took the final four wickets to finish with 4-67.
Launceston keeper Alistair Taylor, who took six catches, said he was grateful to still have Smith's services after the PGA pro recently took up a new role.
"He bowled really well, challenged the stumps and got some caught behinds," Taylor said.
"He's just moved to Barnbougle so he's going to be based there for the rest of the season but we're really fortunate his employers said 'you can play cricket mate'.
"We thought at one stage we probably wouldn't have him - obviously a new job and Barnbougle's Barnbougle as well - but we're really fortunate his employer obviously likes cricket."
The Lions batted another 53 overs to round out the day on 4-213 with two wickets in two balls to Jeremy Jackson one of few highlights for South.
Cam Lynch continued a career-best season with 84 not out and put on an unbeaten 110-run stand with George Maguire (64*).
With Lynch missing day one last Saturday, Maguire had been set to return to the twos before Dihan Cloete's Greater Northern Raiders call-up paved the way for the Lion returnee's highest A-grade score.
"He's been away, done uni, all that sort of thing and moved back for work," Taylor said.
"I'm really happy for the bloke, he's trained really hard and he's such a great guy, he's one of the better blokes at the club out of a good bunch."
Harris said his side had been just one good partnership away from making a real fist of the chase but gave full credit to the unbeaten ladder-leaders.
"They kept coming and they took hold of their catches - something we weren't able to do in the first innings - so fair play to them, they were just too good," he said.
"We played patches of really good cricket that'll hopefully put us in good stead for the next couple of games, but not good enough for long enough really."