Zak Butters took home his second John Cahill Medal on Friday evening. Image: Matt Sampson.

Each season the John Cahill Medal is award to the player judged to be Port Adelaide's best and fairest player in the AFL.

How votes are calculated: Following the completion of each game, a three-person panel, made up of Senior Coach Ken Hinkley, each player’s respective line coach and General Manager – Football Chris Davies cast their votes. Each player’s performance is rated between 0-5, with a maximum of 15 and minimum of zero votes awarded per player, per game. 

Round 1 votes v West Coast 
11. Rozee, 9. Zerk-Thatcher, 8. Burton, Butters, Dixon, Farrell, Soldo, 7. Bergman, 6. Horne-Francis, Houston, Marshall, 5. Byrne-Jones, 4. Aliir, Drew, 3. Boak, Finlayson, Jones, Mead, Ratugolea, Rioli, Wines, 1. McEntee 

Round 2 votes v Richmond 
11. Zerk-Thatcher, 10. Butters, 9. Byrne-Jones, Drew, 7. Marshall, Rozee, Wines, 6. Dixon, Finlayson, Houston, Soldo, 4. Bergman, 3. Aliir, Boak, Burgoyne, F Evans, Ratugolea, 2. Farrell, Mead, 1. Jones 

Round 3 votes v Melbourne 
9. Drew, 7. Farrell, 6. Byrne-Jones, Rozee, 5. Boak, 4. Butters, Dixon, Wines, Zerk-Thatcher, 3. Aliir, Houston, McEntee, Ratugolea, Rioli, 2. Bergman, Finlayson, Burton, Soldo, 1. Burgoyne, Marshall, Mead 

Round 4 votes v Essendon 
15. Rozee, 12. Horne-Francis, 10. Byrne-Jones, 9. Houston, Soldo, 8. Butters, 7. Rioli, 6. Drew, Finlayson, Georgiades, 5. Aliir, Burton, 4. Farrell, Zerk-Thatcher, 3. Burgoyne, Dixon, Marshall, Mead, Ratugolea, 2. Bergman, Jones, McEntee 

Round 5 votes v Fremantle 
9. Aliir, Houston, 7. Farrell, 6. Georgiades, Rozee, Zerk-Thatcher, 5. Butters, Soldo, 4. Bergman, Burgoyne, Drew, Horne-Francis, Ratugolea, Rioli, 3. Burton, 2. Jones. 1. Byrne-Jones, Dixon, Mead, Wines 

Round 6 votes v Collingwood 
7. Butters, 5. Aliir, Horne-Francis, 4. Burgoyne, Houston, 3. Marshall, 2. Bergman, Byrne-Jones, Farrell, 1. Drew, McEntee, Zerk-Thatcher  

Leaderboard after Round 6

1. Rozee – 45 votes
2. Butters – 42 votes
3. Houston – 37 votes
4. Zerk-Thatcher – 35 votes
5. Byrne-Jones/Drew – 33 votes 

Round 7 votes v St Kilda 
9. Burgoyne, Dixon, 8. Houston, 7. Drew, 6. Boak, Farrell, Sweet, 5. Bergman, Butters, Byrne-Jones, Horne-Francis, Jones, Rioli, Wines, Zerk-Thatcher, 4. Rozee, 3. Georgiades, Powell-Pepper, Ratugolea, Williams, 2. Mead, 1. Aliir 

Round 8 votes v Adelaide 
9. Butters, 6. Bergman, 5. Houston, 4. Boak, Sweet, 3. Horne-Francis, Ratugolea, Wines, Zerk-Thatcher, 2. Jones, 1. Byrne-Jones, Drew, Farrell, Georgiades, Rioli 

Round 9 votes v Geelong 
11. Butters, 10. Horne-Francis, Rioli, 8. Wines, 7. Ratugolea, 6. Aliir, McEntee, Visentini, 5. Farrell, Mead, 4. Byrne-Jones, Marshall, 3. Boak, Burton, Drew, Georgiades, Houston, Sinn, Zerk-Thatcher, 2. Dixon, Finlayson, 1. Bergman 

Round 10 votes v Hawthorn 
10. Horne-Francis, 9. Houston, 8. Rioli, 7. Butters, Byrne-Jones, 4. Drew, Farrell, Marshall McEntee, Sinn, 3. Boak. Burgoyne, Dixon, Mead, 2. Aliir, Ratugolea, 1. Bergman, Burton, Visentini, Zerk-Thatcher 

Round 11 votes v North Melbourne 
11. Marshall, 9. Horne-Francis, Wines, 8. Byrne-Jones, Ratugolea, 6. Butters, 5. Aliir, Boak, McEntee, 3. Farrell, Georgiades, Houston, Mead, 4. Burgoyne, Zerk-Thatcher, 1. Burton, Drew, Rozee 

Round 12 votes v Carlton 
9. Georgiades, 8. Horne-Francis, 5. Aliir, Ratugolea. 4, Bergman, 3. Burgoyne, Houston, Mead, Wines, 2. Burton, Butters, Zerk-Thatcher, 1. Boak, Byrne-Jones, Drew, F Evans, Farrell, Marshall 

Leaderboard after Round 12 

1. Butters – 82 votes
2. Horne-Francis – 72 votes
3. Houston – 68 votes
4. Byrne-Jones – 59 votes
5. Brandon Zerk-Thatcher – 53 votes 

Round 13 – BYE 

Round 14 votes v GWS 
9. Houston, 7. Byrne-Jones, 6. Georgiades, 5. Farrell, 4. Mead, 3. Aliir, Bergman, Burgoyne, Drew, Zerk-Thatcher, 2. McEntee, 1. Horne-Francis, Marshall, Ratugolea, Rozee, Soldo, Wines 

Round 15 votes v Brisbane 
8. Butters, 5. Georgiades, 4. L Evans, Horne-Francis, 3. Bergman, Drew, Mead, Rozee, 2. Houston, Lord, 1. Finlayson, Narkle, Ratugolea, Sinn 

Round 16 votes v St Kilda 
9. Horne-Francis, Zerk-Thatcher, 7. Aliir, 6. Butters, 5. Drew, Narkle, Rozee, 4. Farrell, Sweet, 3. Bergman, Byrne-Jones, Jones, Mead, 2. Wines, 1. Boak, L Evans, Finlayson, Houston, Lord, Sinn 

Round 17 votes v Western Bulldogs 
11. Rozee, 10. Georgiades, 9. Butters, Zerk-Thatcher, 8. Aliir, 7. Wines, 6. Byrne-Jones, Horne-Francis, Jones, 5. Bergman, 4. Drew, Marshall, Mead, 3. Burgoyne, Houston, Lord, 2. L Evans, Farrell, Narkle 

Round 18 votes v Gold Coast 
7. Aliir, 5. Houston, Rozee, 4. Butters, F Evans, 3. Bergman, Boak, Burgoyne, Drew, L Evans, Narkle, 2. Lord, Mead, Sweet, Zerk-Thatcher, 1. Byrne-Jones, Dixon, Farrell, Jones, Wines 

Leaderboard after Round 18

1. Butters – 96 votes 
2. Horne-Francis – 86 votes
3. Houston – 80 votes
4. Byrne-Jones – 69 votes
5. Zerk-Thatcher – 65 votes 

Round 19 votes v Richmond 
9. Dixon, 8. Rozee, 7. Aliir, Burgoyne, 6. Bergman, L Evans, Georgiades, 5. Butters, Drew, Houston, 4. Boak, F Evans, Sweet, 3. Byrne-Jones, Mead, Rioli, Wines, Zerk-Thatcher, 2. Narkle, 1. Horne-Francis 

Round 20 votes v Carlton 
9. Aliir, 8. Bergman, Wines, 7. Drew, Zerk-Thatcher, 6. Byrne-Jones, Georgiades, Horne-Francis, Ratugolea, Rozee, 5. Houston, 4. Boak, Butters, Farrell, 3. F Evans, Mead, Rioli, Sweet, 2. Burgoyne, 1. L Evans 

Round 21 votes v Sydney 
11. Drew, 10. Farrell, Horne-Francis, Houston, 9. Butters, Rioli, 8.Dixon, Georgiades, Jones, Wines, 7. Rozee, 6. Aliir, Ratugolea, Sweet, Zerk-Thatcher, 4. Bergman, F Evans, Mead, 3. Boak, Burgoyne, Byrne-Jones, L Evans, 1. Narkle 

Round 22 votes v Melbourne 
9. Horne-Francis, 7. Butters, 6. Boak, 5. Aliir, Bergman, Houston, Rozee, 4. Byrne-Jones, 3. Dixon, Drew, L Evans, Ratugolea, 2. Farrell, Mead, Narkle, Wines, 1. Burgoyne, F Evans, Jones, Sweet 

Round 23 votes v Adelaide 
12. Butters, 9. Horne-Francis, 7. Aliir, Byrne-Jones, Sweet, Zerk-Thatcher, 6. Bergman, Burgoyne, Rozee, 5. Drew, Wines, 4. F Evans, Houston, 3. Boak, Burton, Dixon, Farrell, Ratugolea, Rioli, 1. Mead, L Evans 

Round 24 votes v Fremantle  
8. Zerk-Thatcher, 7. Butters, Horne-Francis, Sweet, Wines, 6. Bergman, Drew, L Evans, 5. Aliir, Burton, Mead, Rioli, 4. Byrne-Jones, 3. Boak, Burgoyne, F Evans, Farrell, Georgiades, McEntee, Ratugolea, 1. Rozee 

Leaderboard after Round 24

1. Butters – 153 votes 
2. Horne-Francis – 134 votes 
3. Houston – 117 votes 
4. Aliir – 112 votes 
5. Rozee – 108 votes 

Qualifying Final votes v Geelong 
7. Bergman, Horne-Francis, 5. Burton, 3. Sweet, 2. Boak, Byrne-Jones, 1. Aliir, Drew, Georgiades, Rioli, Rozee, Wines 

Semi-Final votes v Hawthorn 
11. Burgoyne, 8. Rioli, Sweet, 7. L Evans, Georgiades, Horne-Francis, 6. Aliir, Byrne-Jones, Drew, Rozee, 5. Bergman, Ratugolea, Zerk-Thatcher, 4. Butters, Jones, 3. Sinn, Wines, 2. Boak, Mead, 1. Narkle 

Preliminary Final votes v Sydney 
10. Aliir, 4. Horne-Francis, Jones, Sweet, 3. Burgoyne, Drew, Rozee 2. Boak, Burton, Butters, L Evans, Wines, 1. Bergman, Byrne-Jones, Dixon, Georgiades, Narkle, Rioli 

Final Leaderboard 

1. Butters – 159 votes 
2. Horne-Francis – 152 votes 
3. Aliir – 129 votes 
4. Rozee – 118 votes 
5. Houston – 117 votes