Lyon has been ruled out of the remainder of the Ashes 2023 series due to a calf strain.
No replacement has been named to Australia's squad, which means Todd Murphy will almost certainly replace Lyon for the third Test against England.
Reserve batter Matt Renshaw has been released from the squad but will remain on standby in the UK.
Lyon, who claimed eight wickets in Australia’s first Test victory at Edgbaston, tore his calf while fielding on Day 2 at Lord’s. While the ace off-spinner wasn’t able to bowl for the remainder of the match, he inspired his teammates by hobbling out to bat in the second innings.
Meanwhile, Lyon has backed Murphy to combat England's all-out attacking approach. The 22-year-old impressed one and all on his maiden Test tour of India earlier this year, picking up 14 wickets at 25.21 in four Tests.
"His stock ball is good enough in international cricket. We have seen that in India in arguably the hardest place to bowl spin," Lyon quoted as saying by cricket.com.au. "It will be a different challenge with the England batters.
"If they do come at him, it provides Todd with a decent challenge. But a chance to leave his footmarks here in England. It is a big Ashes series, he is excited by the opportunity," he added.
Lyon further said that he would available to guide Murphy if required.
"I sat with Todd in the last session there (on day four) and spoke about spin bowling as we do. I have a lot of confidence in Todd. He is a great kid. He is willing to learn along the way," he stated. "I have told him my phone is always on, it doesn't matter if I am sitting in the changeroom with him or I am sitting at home watching it in bed."
Australia coach Andrew McDonald all but confirmed that Murphy will feature in Australia’s playing XI for the third Ashes Test.
"As you saw (on Sunday), at certain times, we had to do it differently without Nathan Lyon down the other end, which we've been so used to," McDonald said. "At times it looked a little bit chaotic so we do like to have that spin option."
The third Test will be played at Headingley from July 6.
Australia squad: Pat Cummins (c), Scott Boland, Alex Carey (wk), Cameron Green, Marcus Harris, Josh Hazlewood, Travis Head, Josh Inglis, Usman Khawaja, Marnus Labuschagne, Mitch Marsh, Todd Murphy, Michael Neser, Jimmy Peirson, Steve Smith (vc), Mitchell Starc, David Warner
(cricket.com.au inputs)