Arsenal manager Arsene Wenger says he is hopeful of making two more signings before the transfer widow closes, with one of them expected to be Real Madrid midfielder Nuri Sahin.
The Gunners have lost both Robin van Persie and Alex Song this summer, with Song completing his switch to Barcelona on Monday.
At the weekend, Wenger said he would try to bring in a midfield replacement for the Cameroon international, with Sahin widely tipped to arrive on loan for the season.
And the Arsenal boss said he also wanted to add a defender to his ranks. He told Arsenal's official website: "We are looking to bring one more midfielder in, of course, and maybe one defender as well because we still feel we are short in some positions."
Injuries to Bacary Sagna and Laurent Koscielny have left Wenger with a slight shortage of defensive options, especially at right-back.
Arsenal failed to find the net against Sunderland on the opening day, drawing 0-0 at the Emirates, and while Wenger admitted some disappointment with the display, defender Per Mertesacker insisted the side would soon gel, with plenty more to come from new arrivals including Lukas Podolski.
"It was tough for him [Podolski] because it was his first game up front," Mertesacker said. "I think he will get used to the game, switch on quickly and score a lot for us.
"You have seen that he has a good technique and he is good in possession. We have the players who can pass him the ball. He is a good finisher too, and we will see that in a couple of weeks.
"We saw a lot of misunderstandings, especially in the first half. So we need a bit of time, especially with the new players. We had a few new players who were playing their first game over 90 minutes. But I think it is coming."