The 24-year-old from Oban carded a second successive 71 at Bay Hill in Orlando for a two-under-par total, which was set to leave him in or around the top 20 at the halfway stage.
By making it to the weekend in the $9.3 million event, MacIntyre virtually ensured he won’t drop below his current position of 43rd when the world rankings are updated on Monday.
At the same time, the left-hander set up the chance to improve on that position in his bid to be in the top 50 on 29 March, when the final batch of invitations for this year’s Masters will be determined.
MacIntyre had the safety net of no cut when he faced a stiff test to start a run of big events in the US in last week’s WGC-Workday Championship at The Concession in Florida.
He finished in a tie for 61st behind Collin Morikawa, admitting it “wasn’t that good of a week” but, at the same time, felt there were “a lot of positives” for the remainder of his trip.
That was vindicated over the first two days at Bay Hill as MacIntyre negotiated the opening 36 holes without putting himself under any real stress.
His opening effort on Thursday contained 15 pars, two birdies and one bogey, with the second circuit confirming that he’s feeling comfortable at the home of the late Arnold Palmer.
After starting at the tenth, the young Scot birdied the par-5 12th before bouncing back from a bogey at the 15th with gains at both the 16th and 18th, where he holed an 18-footer.
He was probably slightly disappointed that a couple of birdie chances went abegging in a run of six straight pars to start his back nine before dropping a shot at the par-3 seventh after missing the green.
On a day when Martin Laird who had opened with a 69 to sit just three shots off the overnight lead, was among the later starters, Russell Knox also signed for a 71 to sit inside the projected cut mark on one-over.
Having opened with a 74, he badly needed something in red figures and it was mission accomplished, helped by back-to-back birdies on his back nine.
Canadian Corey Conners, who had started the day tied for the lead with Rory McIlroy, backed up his opening 66 with a 69 to move to nine-under.
“It was really solid today,” said Conners, the 2019 Valero Texas Open champion after an effort that was illuminated by an eagle-3 from around 20 feet at the 16th.
On heading into the weekend, he added: “I haven't really been in this position a lot, but I have a lot of confidence in my game.”
As does Norwegian Viktor Hovland, who is in the mix yet again on the US circuit after opening rounds of 69-68. “It's been fun,” he said of finishing in the top five in his last three events.
Playing in this tournament for the first time in four years, Paul Casey carded a 69 to sit on five-under, one better than two other Englishmen, Lee Westwood and Matthew Fitzpatrick.