Organiser of the English second-tier division Sky Bet Championship, announced the Team of the Week on their Twitter handle on Sunday.
Ajayi was the hero for the Baggies after grabbing the only goal of the game with a stoppage time strike which secured a 1-0 win at Peterborough.
The Super Eagles defender was placed in the middle of a four-man defence in the Team of the Week that is in a 4-4-2 formation.
The win took West Brom to second in 13 points in the league table after five games played.
By James Agberebi