The striker is expected to return to action against Aston Villa on Monday night and his manager is backing him to find top form for the rest of the season
The France international has scored 11 goals already this campaign but has missed Arsenal’s last two games against Tottenham and Cardiff.
Giroud is expected to return on Monday when Arsenal travel to Aston Villa, knowing a win will take them back to the top of the table, and Wenger is backing the Frenchman to fire.
“He was a bit tired recently but now he is refreshed, he is back, and I am sure he will have a major impact on the second part of the season,” the Gunners boss told reporters.
“When you speak to the coaches after the game they say 'oh, what a client he is'. He has qualities that the rest of the squad has not got. He always gives us that strength.
“We have small players who combine quickly, so to find someone who can hold it, keep the ball, make some room for other players. well he does that very well. He gives us a very good balance.
“[He reminds me of] Alan Smith in the way he holds up the ball, in his distribution and his goalscoring.”
Injuries to Theo Walcott and Nicklas Bendtner have seen Arsenal linked with a move for a striker in the January window, but Wenger was happy to pay tribute to Giroud's qualities.
“He's a tough, tough boy. Even when the medical people say he should rest, he says: 'I'm alright'. He needed five stitches after the game at Newcastle,” he added.
“He played the whole game there with an open ankle and without complaining. And when I took him off, he didn't want to come off! He's tough.
“He's always ready for a fight, even when he's tired.”