The French forward suffered an ankle sprain against his former club, who won 2-1 at the Emirates.
But Unai Emery insists there is not considerable concern over the long-term health of the player.
“We are thinking the Lacazette injury is not serious,” Emery said. “He decided with the doctor and with me not to take a risk.
“It is better in pre-season to do that. It’s in his ankle, it’s a sprain. He will be assessed over the next few days but it is not serious.”
“It was a decision made between the players and us that it’s not a good moment to play because their mind is not 100 per cent here,” Emery declared.
“It’s a very personal circumstance and the most important thing is that they now feel good, feel safe and feel calm with their family.
“After a couple of days they can come and start properly with the squad again.”
While Nicolas Pepe could soon join to become the club’s record signing at £72m.
“We are thinking about how we can improve the club,” Emery added when quizzed on the Ivorian.
“Pépé is a very good player and we are only thinking about players that can improve this squad and give us different conditions.”
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