The meeting took place in Leicester and ended with a score of 3: 1.
The hosts featured Patson Duck (11th minute), James Maddison (21st) and Oninye Ndidi (33rd).
The Warsaw team scored only with a goal by Filip Mladenovic (26th), who finished off the ball into the opponent's goal after an unrealized penalty by Mahir Emreli.
Brandon Rogers' wards scored eight points and topped the group C standings, overtaking Spartak Moscow (7).
Legia is in last place in the quartet (6).
Earlier it was reported that Lokomotiv lost the chance to reach the playoffs of the Europa League.