Just three days after their European tie ended all-square, both teams were back to do battle for league points. Each manager made several changes, no doubt with one eye on next week's second leg of their Champions League quarter-final.
"In my brain it is not over, because it is not over mathematically," Wenger said. "It depends on the results of the other teams. I said we would need at least five wins and a draw.
"It is frustrating again because I feel we had a blatant penalty again for a foul on [Cesc] Fabregas, which was not given. You can see it well on television, it is 100% conclusive. We also had a chance in the last minute to kill the game off.
"It was a bit of repetition of Wednesday night. We had problems starting the game, and then got into the game after 30 minutes. Then just before half-time they got the goal and then they defended for every ball in their half and you needed to get back to score a second goal, which was possible.
"We had to throw everything forward and left ourselves open a little on counter-attacks. That was the game basically."
Wenger defended his team selection, which saw five changes from Wednesday night's game, including leaving leading scorer Emmanuel Adebayor on the bench.
"When you don't win the game, you are looking for what could have been different," he added. "It is difficult, but you have to make decisions. With the schedule we have, if you only always play the same XI, it does not work as well."