O'Brien, who amassed a career-best 31 disposals, received 10 votes in the AFL Coaches Association champion player award.
According to the coaches,Collingwood's Nathan Buckley and Geelong's Chris Scott,the Pies had the top four players on the MCG on Saturday night, with Scott Pendlebury (eight votes), mature-age VFL recruit Sam Dwyer (six) and Jarryd Blair (two) also recognised.
O'Brien was one of nine players to be awarded a perfect 10 last round, a rare example of a perfect score for every game.
It was no surprise that Nic Naitanui was one of those to get a perfect 10 following his superb performance, and match-winning goal after the siren, against NorthMelbourne at Patersons Stadium on Friday night.
Dayne Zorko received best-afield honours in the Brisbane Lions' shock victory over Essendon at Etihad Stadium on Saturday.
Lions skipper Jonathan Brown, written off by some as being near the end of his illustrious career, was awarded three votes, as was Irishman Pearce Hanley, who is in equal eighth spot in the coaches' award leaderboard.
The outright leader is Gary Ablett, who was adjudged best-on-ground in Gold Coast's win over the Western Bulldogs at Metricon Stadium on Saturday night.
Suns prodigy Jaeger O'Meara polled votes for the third time this year, receiving four against the Dogs, while another young gun, Richmond's Nick Vlastuin, was awarded votes in just his fourth AFL game.
Sydney Swans pair Dan Hannebery (10) and Kieren Jack (eight) were deemed the top two players in their team's draw with Fremantle at the SCG on Saturday night. They sit second and equal-third respectively in the coaches' award.
West Coast v North Melbourne
10 Nic Naitanui (WCE)
7 Darren Glass (WCE)
4 Daniel Wells (NM)
3 Ben Cunnington (NM)
2 Brent Harvey (NM)
2 Josh Hill (WCE)
1 Aaron Black (NM)
1 Lachie Hansen (NM)
Essendon v Brisbane Lions
10 Dayne Zorko (BL)
6 Dyson Heppell (Ess)
6 Jack Redden (BL)
3 Jonathan Brown (BL)
3 Pearce Hanley (Bris)
2 Brendon Goddard (Ess)
Hawthorn v GWS Giants
10 Sam Mitchell (Haw)
8 Jarryd Roughead (Haw)
6 Jordan Lewis (Haw)
2 Brent Guerra (Haw)
2 Jack Gunston (Haw)
1 Taylor Adams (GWS)
1 Brian Lake (Haw)
Gold Coast v Western Bulldogs
10 Gary Ablett (GC)
8 Rory Thompson (GC)
6 Adam Cooney (WB)
4 Jaeger O'Meara (GC)
1 Ryan Griffen (WB)
1 Dion Prestia (GC)
Collingwood v Geelong
10 Harry O'Brien (Coll)
8 Scott Pendlebury (Coll)
6 Sam Dwyer (Coll)
2 Jarryd Blair (Coll)
2 Mathew Stokes (Geel)
1 Andrew Krakouer (Coll)
1 Tom Lonergan (Geel)
Sydney v Fremantle
10 Daniel Hannebery (Syd)
8 Kieren Jack (Syd)
3 Nathan Fyfe (Frem)
3 Michael Johnson (Frem)
3 Josh Kennedy (Syd)
2 Nick Malceski (Syd)
1 Jarrad McVeigh (Syd)
Carlton v Port Adelaide
10 Marc Murphy (Carl)
5 Ed Curnow (Carl)
4 Lachie Henderson (Carl)
4 Mitch Robinson (Carl)
4 Chad Wingard (Port)
2 Jeff Garlett (Carl)
1 Andrew Moore (Port)
Richmond v Melbourne
10 Brandon Ellis (Rich)
8 Nick Vlastuin (Rich)
3 Trent Cotchin (Rich)
3 Daniel Jackson (Rich)
2 Aaron Davey (Melb)
2 Ty Vickery (Rich)
1 Shane Edwards (Rich)
1 Dean Terlich (Melb)
Adelaide v St Kilda
10 Rory Sloane (Adel)
7 Richard Douglas (Adel)
5 Sam Jacobs (Adel)
4 Leigh Montagna (St K)
2 Dylan Roberton (St K)
1 David Mackay (Adel)
1 Jack Newnes (St K)
LEADERBOARD
41 Gary Ablett (GC)
38 Daniel Hannebery (Syd)
35 Patrick Dangerfield (Adel)
35 Kieren Jack (Syd)
35 Jobe Watson (Ess)
30 Travis Boak (PA)
30 Hamish Hartlett (PA)
29 Pearce Hanley (BL)
29 Scott Pendlebury (Coll)
28 Rory Sloane (Adel)
Ben Collins is a reporter for AFL Media. Follow him on Twitter: @AFL_BenCollins
