The France international scored Arsenal’s second strike in a 3-1 victory over West Ham United at The Emirates on Tuesday night.
He responded very well in the second half because he’s mentally a strong guy
Giroud had made a poor start to the mid-week clash after fluffing a clear-cut chance as he attempted a tame chip.
However, the 27-year-old made amends after the interval, showing strength to hold off Winston Reid and superb close control before firing past Hammers goalkeeper Adrian.
Giroud paid a classy tribute to the 96 Hillsborough victims on the 25th anniversary of the disaster as he celebrated his 14th Premier League goal, and Wenger praised the former Montpellier man.
“Olivier is a great guy with a great mentality,” Wenger said.
Alluding to speculation about Giroud’s private life, the Arsenal manager added: “He has gone through a difficult period, as you know, and I think it affected his game for a while and his confidence.
“I hope that what happened tonight… you could see that he was refreshed tonight and that he was up for it.
“At half-time he came in, he was very very down because he missed a great chance in the first half, but he responded very well in the second half because he’s mentally a strong guy.”
Giroud has scored scored 14 goals and made seven assists in 32 Premier League games this season.
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