Liverpool thrashed Arsenal 3-1 in a crucial game week 27 encounter at the Anfield on March 4. Roberto Firmino, Sadio Mane and Georgio Wijnaldum netted for Liverpool and Danny Welbeck scored for Arsenal.
Alexis Sanchez who is the top scorer in the league and has scored 20 goals in this season so far was introduced in the second half by Wenger against Liverpool.
Speaking about his decision, Wenger said: "Yes (it did backfire) but I felt that in the first half the strikers suffered because we didn't dominate in the midfield and in the second half you could see that it was easier because Danny Welbeck and Olivier Giroud were much better, so it's always debatable.
"The thinking was that we had to go more direct and I wanted to play two players who were strong in the air and after that to bring on Alexis Sanchez in the second half.
"We did go direct in the first half. We didn't create any chances and we didn't make enough of our corners.
"I am strong enough and lucid enough to analyse. I don't deny Alexis Sanchez is a great player - I bought him - but this was my plan.
"The collective performance was not good enough in the first half and that is the more rational explanation.
"I think in the first half we suffered from a lack of competition but it was a game of two halves and in the second half we did well."
Alexis Sanchez provided the assist for Danny Welbeck's goal in the second half which raised the hope of Arsenal fans.
After Sanchez's inclusion into the field, Arsenal's gameplay changed and they were looking more confident with the ball.