New Zealand now has five riders in the top-15 on world cup standings in downhill, the most of any nation.
New Zealand's burgeoning group of downhill racers were all in outstanding form on the brutal and rocky course at Mont Sainte Anne.
Macdonald (MS Mondraker) led the way in sixth place, his best of the season. The Napier rider was very fast over the opening section although he made two small errors through the rocky mid-section before powering home in 4:17.907, less than four seconds behind the winner, American Aaron Gwin who made it three world cup victories on the trot.
"I am pretty stoked with my run today," Macdonald said. "Just a couple of small mistakes meant I narrowly missed the podium but I am just happy to be back up there. It's a good feeling.
"This course is hard. Four minutes 14 was the fastest but it's pretty brutal."
Macdonald said the performance has given him real confidence going forward for next weekend's world cup in Windham.
"From this race I just need to work on getting my suspension dialled and I think it is going to be pretty good from now on I hope.
"That track in Windham is short and kind of physical as well. I did well there last year so hopefully I can get a podium."
Wanganui's Sam Blenkinsop (Lapierre International) sat in the hot seat as the fastest rider for some time after his slick 4:19.161 before the latter riders including Macdonald went faster, finally settling for a season best ninth place.
Dunedin's Justin Leov (Trek World Racing) also pushed into the top 10 for the first time this year with a 4:19.655, just ahead of Christchurch's Cameron Cole (Lapierre International) who was 11th fastest in 4:20.037.
Hawkes Bay rider George Brannigan (DeVinci Global) was 17th in 4:24.135 while Nelson's Kieran Bennett went considerably faster that his qualifying run to be 55th in 4:33.988, the first time he has cracked the top 80 for the finals from the initial 180 entrants.
The Rocky Roads World Cup moves across the border to Windham in upstate New York for both crosscountry and downhill next weekend.
Elite men downhill: Aaron Gwin (USA, Trek World Racing) 4:14.022, 1; Greg Minnaar (RSA, Santa Cruz) 4:15.329, 2; Danny Hart (GBR, Giant) 4:16.162, 3. Also New Zealanders: Brook Macdonald (MS Mondraker) 4:17.907, 6; Sam Blenkinsop (Lapierre International) 4:19.161, 9; Justin Leov (Trek World Racing) 4:19.655, 10; Cameron Cole (Lapierre International) 4:20.037, 11; George Brannigan (DeVinci Global) 4:24.135, 17; Kieran Bennett 4:33.441, 55.
World Cup standings after 4 rounds: Gwin 900, Minnaar 765, Gee Atherton 640. Also: Blenkinsop and Leov 301, equal 11; Cole 296, 13; Macdonald 286, 14; Brannigan 258, 15.