The Uddingston player's 175 was the highest by a Scot in a one-day international, helping the team post their best-ever total en route to victory over Canada in Christchurch.MacLeod's 144-run stand with Matt Machan for the second wicket was also a national record as the Scots reached a massive 341-9 to qualify for the Super Six stage as group winners.
It was a memorable day for MacLeod, particularly since this is the player who was forced to re-invent himself as a batsman while also remodelling a bowling action which was deemed illegal by the ICC.
Despite his individual heroics, the 25 year-old was at pains to emphasise the collective effort which underpinned another commanding display.
There were also batting performances from Machan and Freddie Coleman which on another day would have grabbed the headlines, all the bowlers made a contribution and, just for good measure, Matty Cross equalled a wicket-keeping record.
"It's obviously a special day for me and not one I'll forget in a long time," said MacLeod. "But the record is something to think about in the future because the most important thing is that the team has reached the next stage of the qualifying process.
"Our objective is to qualify for the World Cup and hopefully this is just a step that gets us there."
MacLeod reached his second consecutive international century -he had scored 113 against UAE on Sunday - from just 96 deliveries with eight boundaries.
However, having made it to the three-figure landmark, he went into overdrive to leave Canada's qualification hopes in tatters. The Canadians had needed a big win but their chances were ruthlessly extinguished as MacLeod added another 75 from a further 45 balls, stroking six more boundaries and bludgeoning five maximums.
Machan weighed-in with 68 and Coleman 40 as Scotland passed their previous highest ODI score of 323 against Ireland. There were two more milestones to come as Aberdeenshire and Notts wicket-keeper Cross claimed six catches - equalling the record held by Mark Boucher and Adam Gilchrist - while Majid Haq claimed his 50th ODI wicket.
Canada were eventually dismissed for 171, with Rob Taylor, Iain Wardlaw and Safy Sharif taking two wickets each, as Scotland completed a huge 170-run win. "Calum batted exceptionally well and to score the runs he did without giving a chance was a fantastic effort," coach Craig Wright said. "He has shown a great hunger for runs in this tournament as back-to-back hundreds proves. It was also a great effort by Crossy behind the stumps and overall we are delighted with the performance."