Arsenal manager Arsene Wenger has revealed midfielder Jack Wilshere is unavailable due to a patella injury.
Wilshere missed Arsenal's win over Guadalajara on Sunday and is likely to be on the sidelines for their next game against Viking on Friday.
The England international struggled to make an impact at Euro 2016 after managing just one Premier League start last season, but Wenger claimed Wilshere's latest injury is not serious.
"It's a slight patella problem but I think he should be with us on tour on Thursday," Wenger said. "I hope he will, yes."
Santi Cazorla is another Arsenal midfielder to have struggled with injury, but the Spaniard got more minutes under his belt against Guadalajara.
"He is our technical security in midfield and we missed him for five or six months last season," Wenger said. "At the moment he is not completely there on the fitness front. That's why I took him off at half-time.
"He's a bit behind the others physically but I think he will be alright, maybe not on August 14th, but at the end of August he should be alright," he said, referring to the Gunners' first match of the Premier League season at home to Liverpool.
Wenger was happy with the patience Arsenal showed in a 3-1 victory against Mexican opposition in Los Angeles, with Rob Holding, Alex Oxlade-Chamberlain and Chuba Akpom on the scoresheet.
"Overall I think it was interesting for us because we needed to be patient as they started better than us," Wenger said.
"After 20 minutes we came into the game and we got a comfortable win in the end. It was very interesting to see some young players - we had a very young defence. Overall it was a positive experience for us."
After facing Viking, Arsenal will be in action against Manchester City in Gothenburg on Sunday.