"We need to improve our attacking a lot and play with the intensity we had in the second half," the Romanian told reporters at a press conference.
"Aside from their goal we were good in defence, although we struggled because we didn't have much of the ball.
"We were better in the second half and it was more open. We had chances, but Athletic could have got a second goal on the counter-attack."
Getafe have won just seven of their 29 league games this season.