Arsène Wenger has admitted he remains "cautious" over Jack Wilshere's fitness and has suggested England consider leaving the youngster out for the World Cup qualifier against Moldova with one eye on the more daunting trip to Ukraine four days later.

Wilshere will be named in Roy Hodgson's senior squad for the September fixtures when the party is confirmed on Tuesday and will start against Fenerbahce in the second leg of Arsenal's Champions League qualifying tie on Tuesday evening having been rested from the starting XI at Fulham on Saturday. The 21-year-old is still playing at "90%" according to Wenger after long-standing issues with his ankles: he missed 17 months of football with a problem in his right ankle before returning last autumn and the left joint flared up towards the end of the season.

The midfielder underwent surgery to remove the pins on the original injury over the summer. Although he played a full part in pre-season, he did not complete a 90-minute match before the new campaign and, having played the first half for England against Scotland and in Arsenal's first two matches, Wenger left him out from the start at Craven Cottage. "He was a bit tired but it was more about giving him a rest," said the Frenchman. "It made sense to give him a breather because we're playing every three days at the moment. He is not 100% yet but he is 90%.

"It's an important year for every single player because, if you have a good season, you have a good chance of going to the World Cup but I'm a bit cautious because he's had a few operations. I don't want to make a mistake and overuse him because the ankle is the most important part of any football player. People think it's the knee. It's not; it's the ankle. All the movements come from the ankle. He's had surgery three times so we have to be cautious."

Asked if he was concerned at the prospect of Wilshere playing against Moldova at Wembley and then in Kiev four days later, Wenger added: "No. Because we have a good connection with the medical department. They know him well. Who are England's next two games? That's the key. So don't play him against Moldova...

"I always take medical advice. If the ankle is not inflamed, if he has no pain, then we would not rest the player. If they say there is a little inflamed ankle, we would say: 'OK, let's not.' I would be a bit more cautious [with Wilshere], yes, until we feel he is completely free from any risk. If he gets well through the Fenerbahce game, he will play on Sunday [against Tottenham Hotspur] because there are five days between."

Wenger has warned his players against complacency before the second leg with the Turks, despite having won 3-0 in Istanbul, as they seek to smooth their passage into the group stage of the Champions League for what would be a 16th consecutive season.

The manager will then turn his attention back to strengthening the squad before Monday's transfer deadline and still aspires to add up to three players to his squad. One is likely to be their former midfielder Mathieu Flamini, who spent an hour in talks at the training ground alongside his agent, Darren Dein, on Monday with a view to signing a contract following his release by Milan earlier this summer.

Interest is retained in Real Madrid's Angel di María, Karim Benzema and Mesut Ozil as Arsenal anticipate that Gareth Bale's likely move to the Bernabéu could prompt the Spanish club to trim their squad elsewhere, with all three players currently being touted to potential suitors. Arsenal are also interested in Newcastle's Yohan Cabaye, who is the likeliest arrival for around £17m.

Yet Wenger has expressed frustration at rival managers commenting publicly on prospective moves. "Everybody has a good opinion about what other managers should do but they do not look at themselves," he said. "It's better that you shut up and don't say anything. The key for us is getting in the right additions. It is not just about additions but the right additions. Attitude, focus, the mental aspect in the modern game is vital.

"The market has been difficult this summer for two reasons. One, I have quality players; and two, the competition for players is absolutely massive in the international market. Before, we were privileged – a bit more lonely out there. Now, everybody knows everybody and it is more difficult. It is true when I arrived in England, English clubs did not go on the international market as they do now. But we will try until the end and I am optimistic."