The premiers were in trouble at 3-19, but the pair produced a masterclass, compiling 205 runs.
Evans scored 110 from 118 deliveries, with 11 boundaries, while Hillary plastered 85 off 82.
"100 per cent it would have to be and it could even be a league record," captain Bailey Glass suggested when quizzed if it was a club record.
"It was a chanceless innings by the two of them, you couldn't ask for more, it was super to watch.
"We were 2-15 when Cam came in and he said to me, 'we've just got to knuckle down and make it to drinks', I couldn't do that, but they were outstanding."
It's the third century for Evans with Yackandandah.
He scored an unbeaten 100 at under 16 level in 2014-15 and has a highest score of 122 in first grade against Bethanga.
But the 22-year-old believes this innings is his finest.
"Yeah, I reckon it would be, I didn't give a chance," he replied when asked.
His captain maintains the left-hand bat and left-arm quick has improved markedly.
"He's taken his cricket to the next level, he's going to dominate, I think," Glass revealed.
"He's probably taken it a bit more seriously this year, it's great to see, he's a class above district, I reckon, he's capable of playing provincial."
And Evans agrees that he's lifted his intensity.
"When I'm there I'm more switched on, probably partying a little bit less, which helps," he explained.
Yackandandah finished with 6-261 as opening bowler Will McCoy nabbed 4-51 from eight overs.
In reply, Kiewa scored 154 with Ash Sutherland making 45 from 57 balls, while Glass captured 3-23.
Meanwhile, Baranduda posted a four-wicket win over Eskdale.
The visitors posted 8-129 with debutant JJ Burton making an unbeaten 47 from 80 deliveries, including five boundaries and a six.
Baranduda's Judah Hood and Jayden Barter made 21 apiece as David Holliday took 3-30.
Barnawartha Chiltern defeated Dederang by 46 runs.
The visitors' Dilgaurav Kumar top-scored with 35, but Dederang could only post 130 from 28.5 overs.
Middle order bat Ryan Barker produced a classy 49 from 43 balls, smashing eight boundaries and a six, while Chris Hartshorn snared 3-16.
And Mount Beauty defeated Bethanga.
Mt Beauty elected to bat first on the road, with Paddy Dodd striking 36 from 33 balls.
Bethanga certainly didn't have any issues with the run rate and looked a strong chance at 4-100.
But the home team collapsed, losing 6-20 to be dismissed for 120.
Brad Dalbosco played a patient knock as he tried to rescue the team, making 26 not out from 36 balls.
ALSO IN SPORT
It's been a disrupted start to the season, due to COVID restrictions and weather, but Yackandandah and Mt Beauty remain unbeaten after the opening four rounds, with Bethanga and Barnawartha Chiltern trailing by another win.
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