Mathieu Bodmer's goal just before half-time gave Nice a surprise 1-0 win over Lille at the Allianz Riviera.
It continued what has been a miserable run for Lille in Ligue 1 since the mid-season break, making it three losses and a draw since the league resumed in January.
Girard believes his team, who are third in the French top tier despite their winless streak this year, are close to recapturing their form of 2013.
"How do I sum up that match? Inefficiency on our part. We didn't do what we needed to do," he said.
"We conceded a poor goal at the worst possible time just before half-time and Nice just did what they had to do after that.
"In 2013 we were winning games. In 2014 we are losing.
"I had warriors before and I need to get them back. There is not much lacking but we can't be settling for that."
Nice's win lifted them to 12th and just six points behind fifth-placed Marseille in what is a congested mid-table.
Claude Puel - Nice's head coach - believes he has worked out the keys to beating Lille after the south coast club overcame Girard's side 2-0 in September.
"Lille lacked spontaneity and you just need to work hard as a team to contain them," Puel said.
"This game was also fairly similar to when we beat them in the reverse fixture, where we worked hard and exploited the two opportunities that came our way.
"I hope once we get everyone back and fit again we will be able to play better football but for now it's very good to take three points in our situation."
