Thomas Tuchel questioned Chelsea’s commitment and said they need signings urgently after a 4-0 pre-season defeat by Arsenal in Florida on Saturday.
Gabriel Jesus, Martin Odegaard, Bukayo Saka and Albert Sambi Lokonga scored in a comprehensive Gunners win.
Chelsea manager Tuchel suggested his side may not be ready for their Premier League opener at Everton on 6 August.
“I am far from relaxed,” Tuchel said. “We were simply not good enough. We were simply not competitive.”
The Gunners dominated the match in front of a record 63,811 fans at Orlando’s Camping World Stadium.
Jesus, who joined from Manchester City in a £45m deal on 4 July, put Arsenal ahead after 15 minutes, and three further goals wrapped up a comprehensive win.
Arsenal have now won all three of their matches on their US tour, scoring nine goals.