On 24 April 2013, Lyon was named as the only spinner in the upcoming 2013 Ashes series for the Australian squad. It held true until hours before the first match when he was dropped from out of the lineup in favour of shock debutant Ashton Agar, who then went on to score 98 on his Test debut, which was also a world record for a no. 11 batsman. However, Lyon was recalled to the team for the third Ashes Test, and in the fourth Ashes Test at Chester-le-Street, he took figures of 4/42 on the first day to help restrict England to 238 in their first innings. On 28 December 2013, during the Boxing Day Test match at the Melbourne Cricket Ground, Lyon took his 100th Test wicket and also his first five wicket haul in Australia. He became just the sixth Australian off-spinner to take 100 Test wickets.