Arsène Wenger explained why Arsenal’s decision to shatter their wage structure for Mesut Özil’s new £350,000-a-week contract makes economic sense, as he called upon the playmaker to be the team’s “technical leader”.

The manager has fresh attacking options after the whirlwind that was the January transfer window, although he said Pierre-Emerick Aubameyang may not be able to make his debut against Everton at the Emirates Stadium on Saturday because of illness. Wenger intends to start his other high-profile signing, Henrikh Mkhitaryan.

Premier League: 10 things to look out for this weekend Read more

Özil remains central to Wenger’s plans. The 29-year-old has seen his weekly wage rocket from £140,000, meaning that Arsenal have committed to paying him an extra £10.9m per year. Özil’s deal runs until the summer of 2021. But Wenger said it would be impossible to replace him on the market for less.

“When you let a player go, you have to buy somebody of the same calibre and the wages will be similar,” Wenger said. “On top of that, we have to pay a transfer [fee]. So overall, I think Mesut, for us, was the cheapest option.”

With the mega money, comes increased responsibility. “You expect that he becomes the leader and takes more responsibility to lead the team to success,” Wenger said. “Maybe ‘more’ is not the best possible word but that is what you want. It means he will be the technical leader of the team.”

When Aubameyang is fully fit, it will be interesting to see whether Wenger starts him with his other expensive striker, Alexandre Lacazette – who joined for £52.7m from Lyon last summer. Wenger admitted he could offer no assurances to Lacazette, who has scored nine goals this season.

“I think we don’t score enough goals – that’s our basic problem,” Wenger added. “We’re an attacking team, that’s our DNA. When you are an attacking team, the danger comes when you don’t score. Then, you create your own problems. Everyone will get games. Let’s not forget, for example, that Aubameyang is banned [ineligible] in the Europa League and Mkhitaryan is banned for the League Cup final.”

Wenger’s biggest single issue is to better balance his team so they become more sturdy. The lack of a specialist holding midfielder has long felt like a problem while Wenger admitted the improvements would have to come from within the squad after the failure to sign a centre-half in January. West Brom rebuffed their late move for Jonny Evans.

“Do I regret not getting a defender? Yes, because our defensive numbers are not good enough and that’s where we needed some possible strengthening,” Wenger said. “What I wanted to do [in January], we have done. But I couldn’t do everything. I wanted to do more.

“Defensive strengthening is a huge problem for everybody. Everybody looks for a defender. You look again at Manchester City – they bought again a defender [Aymeric Laporte]. How much money have they spent on defenders in the last three years?”