Donald will name his six captain's picks on Monday following the European Masters tournament at Crans-Montana, where several hopefuls for the biennial matchplay showdown are targeting an automatic berth.
This year's matches will be held in Rome from September 29th until October 1st, with Europe desperate to regain the trophy after their humiliating 19-9 defeat by the United States at Whistling Straits two years ago.
The absences of LIV Golf rebels and Ryder Cup stalwarts Sergio Garcia (43), Lee Westwood (50) and Ian Poulter (47) have left the race for the European team more open than in recent editions.
Jon Rahm (28) and Rory McIlroy (34), via the European points list, have already secured places in the 12-team, as have Viktor Hovland (25) and Tyrrell Hatton (31), through the world points list.
Tommy Fleetwood (32) is currently set to qualify from the world points list, but is skipping the European Masters and could be usurped by Matt Fitzpatrick (28).
The former US Open champion only needs to finish in a tie for seventh with one other player or better to snatch the spot and leave Fleetwood needing a pick, alongside fellow former Ryder Cup stars Shane Lowry (36) and Justin Rose (43).
The race for the third and final place on the European list is far less clear-cut.
Scotland's MacIntyre holds a 126-point lead over German Yannik Paul (29) and both players would be sure of a Ryder Cup debut with victory in Switzerland on Sunday.
Pole Adrian Meronk (30) and Victor Perez (30) of France both need at least top-two finishes to have any chance, while rising Danish star Rasmus Hojgaard (22) and Spain's Adrian Otaegui (30) need to win.
All eyes on Donald
An automatic place would save any of that sextet having to sweat over Donald's decision on Monday.
The former world number one is expected to pick whoever misses out of Fleetwood and Fitzpatrick, alongside Rose, Lowry and possibly big-hitting Sepp Straka (30) of Austria.
Others have been tipped for a possible wildcard selection despite being out of the running for automatic qualification, including Ramus Hojgaard's (22) twin brother Nicolai, Irishman Seamus Power (36) and former Ryder Cup winner Alex Noren (41).
Donald may opt for an even more left-field choice.
Sweden's Ludvig Aberg (23), who only turned professional in June, could force his way into the reckoning.
Aberg, who was the amateur world number one before joining the pro ranks, has posted top-four finishes on both the PGA Tour and European Tour in the last two months.
"All those (Ryder Cup) conversations are very flattering," said Aberg, who will play with Ryder Cup vice-captains Edoardo Molinari and Nicolas Colsaerts in Crans-Montana.
"It would mean the world. As a young person growing up in Europe, I watched the Ryder Cup for so many years.
"It's a dream come true if you were to be picked for it once in your career. So I would love it, but it's not up to me."
Donald will have tough calls to make as he bids to supplement the obvious firepower of Rahm, McIlroy and the in-form Hovland.
The USA have not lifted the trophy on European soil since 1993 but will land in Italy as favourites, with three of this year's major champions, including LIV star Brooks Koepka (33), and world number one Scottie Scheffler (27) in their ranks.
