Senior coaches Ken Hinkley and Scott Watters awarded Westhoff six votes for his game-saving efforts in the final quarter.
Westhoff's three crucial marks helped stifle the Saints momentum and kicked Port out of danger late in the match.
Vote for Westy in this week's Lifebroker Mark of the Year nominations
St Kilda's Jack Steven also polled six votes.
Westhoff's effort has seem him rocked into third place among his Power teammates on the AFLCA voting board, still trailling Travis Boak in second place on 39, and Chad Wingard who extended his lead with another four votes.
He now has 44 votes in total.
Tom Jonas (three votes) and Matthew Broadbent (two) also polled from the Power.
Leigh Montagna (four), Ben McEvoy (three) and Nick Dal Santo (two) were St Kilda's other vote recipients.
St Kilda v Port Adelaide AFLCA voting
6 - Westhoff (PA)
6 - Steven (Stk)
4 - Wingard (PA)
4 - Montagna (Stk)
3 - Jonas (PA)
3 - McEvoy (Stk)
2 - Broadbent (PA)
2 - Dal Santo (Stk)
Port Adelaide AFLCA leader board (after Round 17)
44 - Wingard (6,1,6,3,4,1,2,6,8,3,4)
39 - Boak (4,4,10,4,8,8,1)
36 - Westhoff (10,8,9,3,6)
30 - Hartlett (9,2,9,10)
23 - Brad Ebert (3,2,1,2,10,5)
