Atletico and Arsenal played out a 1-1 draw in the first-leg of their Champions League semifinal, with both teams converting penalties.
Le Normand said afterwards: "Given how we played, especially in the second half, we could have won the match.
"They played well too, but with the energy we put in, we could have expected a little more today."
Teammate Marcos Llorente also said: "Absolutely (the tie is wide open). They dominated the first half, and we dominated the second. We need to build on that second half.
"We struggled to win the ball back and were rushing things in the final third. That comes back to haunt you because we don't create that many chances, and we failed to capitalise on the ones we had. We improved in the second half, and that's what we'll take away from this.
"We need to step up our intensity and look to create more one-on-one situations in the final third –that's what keeps you in the game."