Pompey's pre-season friendly at Leyton Orient will now take place behind closed doors.
Danny Cowley's side continue their preparations for the 2022/23 campaign at Brisbane Road on Tuesday evening (7pm kick-off).
Temperatures are expected to reach as high as 40C and the home side made the decision after consulting with their safety advisory group.
Leyton Orient chief executive Mark Devlin said: “With spectator safety our highest priority, we have made the difficult decision to play the game behind closed doors.
“With Brisbane Road accessible mainly via public transport, the severe heat could have likely implications on those travelling to the game, as well as expected widespread delays.”
Orient are offering a free stream of the game on their YouTube channel.