no you're not allowed to play a game with only one defender (any position) because the formation has the red exclamation point on it
Your allowed to play 1 x DC as long as you have both DL and DR as well
LEAGUE WINNER 8
LEAGUE RUNNER UP 5
CUP WINNER 4
CUP RUNNER UP 4
C.L. WINNER 2
C.L. RUNNER UP 4
TREBLES 1
SUPER CUP WINNER 2
CUP DOUBLES 3
CUP TREBLES 1