Hairs, who made his senior international debut against India A in Glasgow 24 hours earlier, made an accomplished 135 as he propelled the hosts to 267 all out. Gregor Maiden provided stout support with 35, but it was Hairs who stole the show.
Stuey Davidson then snapped up three Shire wickets to snuff out any prospect of a fightback. Tony Weed was the only Broughty Ferry batsman to offer meaningful resistance, reaching 42 in their reply of 141.
The Watsonians revival continued as they swept aside the challenge of Dunfermline with ease. Skipper Steve Paige bagged three wickets to send the Knights hurtling to 136 all out.
Then new Scotland squad youngster Ryan Flanigan struck a fine 58 to guide 'Sonians to glory with only three men out and almost 17 overs in hand.
Preston Mommsen hit an unbeaten 58 to carry Carlton to a nervy two-wicket triumph over struggling champions Aberdeenshire.
Pro Michael Parlane (70) and Neil MacRae (60) had inspired the Dons to 237 for five, but, thanks to Mommsen, the capital crew claimed the points in the last over.
Greenock's woes continued as Uddingston produced a slick performance to claim victory at Glenpark.
The home side's meagre total of 131 owed much to a fine display from the Bothwell pace bowlers for whom Paul Hoffmann and Amir Gul claimed four and three wickets respectively.
However, equally noteworthy was the effort of skipper Ricky Bawa who conceded only five runs – the most miserly ten-over spell in SNCL history.
Andy Hislop at least dug in for Greenock with a battling 41 which carried his team to the brink of a triple-figure total for the first time in their last three matches. However, it still required a 33-run stand between Greenock's last pair to carry the score beyond that modest landmark.
And their ultimate tally was no real challenge to Uddingston, who won with more than 22 overs to spare.
The biggest upset of the day came in the First Division table-top clash at Goldenacre, where Arbroath out-gunned pacesetters Heriot's.
A healthy crowd were superbly entertained by a thrilling Glasgow derby against Clydesdale at Hamilton Crescent.
And they were rewarded with the result they wanted as West carved out a thrilling four-wicket win with two balls to spare. Chasing Dale's 255, the home side slumped to 41-2 but skipper Ian Young led the fightback with a hard-hitting 70.
His departure saw Neil Williams carry the mantle with 65 before overseas amateur Neil Bisman struck the winning runs in the final over.
In a low-scoring but drama-packed encounter, the picture had looked bleak for the visitors as they crashed to 101 all out. But they staged a remarkable fightback to claim a four-run success.
Stand-in skipper Calvin Burnett emerged as the hero, along with bowlers Benny McGill and Craig Ramsay.
Burnett produced a brave knock of 36 not out as wickets tumbled around him, then McGill and Ramsay shared seven cheap scalps to complete the amazing salvage job.