Unai Emery will decide on Saturday whether Nicolas Pepe and Alexandre Lacazette can feature against Newcastle on Sunday.
Pepe completed a club-record £72m move to Arsenal from Lille last week and has been training with the first team, while Lacazette has resumed training over the past few days after suffering an ankle injury in a pre-season friendly against Lyon.
The Arsenal boss says both will undergo late fitness tests ahead of Sunday's game at St James' Park, live on Sky Sports Premier League.
"We played the pre-season progressively, including the players who came in late. On Sunday we will start with the players that I am convinced are 100 per cent," he said.
"For some players it is impossible to achieve that performance because they arrived late or are now training after being injured.
"Lacazette trained yesterday and today but I don't know know if he can play on Sunday, we will check tomorrow.
"Pepe has been training and working with us a for a week. I want him to feel good with his partners in the team and the coaches because we train differently to how he worked in Lille.
"I want to give him the best moment to play with us and make his debut. Maybe this will be on Sunday, but I will decide tomorrow."
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Emery delighted by Arsenal's summer recruitment
The Gunners boss also said he has been delighted by the club's organisation and effort in the transfer window, which concluded with the Deadline Day arrivals of David Luiz and Kieran Tierney.
"I am delighted with our work. The club did very well to get the best players to help us and make us stronger. We start on Sunday and will look to see the response of our players," he added.
Emery: New youngsters as exciting as new signings
The Spaniard also stressed the importance of the new crop of youngsters at Arsenal and the affect they can have on the first-team in addition to the new signings.
"I want to say to our supporters I am very excited and enthusiastic with Pepe, David Luiz, [Dani] Ceballos, [Gabriel] Martinelli, Kieran Tierney but also with [Joe] Willock, Reiss Nelson, Bukayo [Saka], with Lacazette, [Pierre-Emerick] Aubameyang, everybody! With [Bernd] Leno, with Emiliano [Martinez], with Matt [Macey].
"We need every player and I want to achieve with every player our best performance. My challenge is to achieve some titles in my present and future here and go to the Champions League.
"My first, first objective is to improve each player in his career."
'We have to reduce gap to Man City and Liverpool'
Emery added that while the club's main objective is to qualify for next season's Champions League, he wants his squad to close the gap on runaway leaders Manchester City and Liverpool from last season.
"We are delighted with our players. Our ambition and motivation is to do the best possible in the all the competitions, the most important of these is the Premier League.
"Our first target is to be in the top four, we reduced the distance last season. Manchester City and Liverpool are stronger than the others at the beginning.
"We want to compete with them and reduced the points gap. Tottenham, Manchester United and Chelsea have the same objectives.
"Last year the difference was really small and the challenge now is for us to achieve a top-four finish.
"Other teams are coming back, signing new players and working very well. Everton, West Ham, Leicester, Wolverhampton, Watford.
"The Premier League is the best competition in the world. We are going to work to compete and get into the top four."