Branislav Ivanovic will not face any suspension despite being sent off in Chelsea's Community Shield loss to Manchester City on Sunday.
Ivanovic was given his marching orders towards the end of the first half at Villa Park when referee Kevin Friend showed him a straight red card for a foul on Aleksandar Kolarov.
It was thought Ivanovic would be banned for three matches, starting with Chelsea's opening Premier League fixture at Wigan next Sunday.
However, it has been confirmed that the Football Association changed its rules after an incident during an Amsterdam Tournament in 2006, when Manchester United pair Paul Scholes and Wayne Rooney were both sent off against Porto and ended up serving three-match bans.
As the rule change covered all non-competitive pre-season fixtures, including the Community Shield, it means Ivanovic will be free to play at the DW Stadium.
The news will come as a boost to Roberto Di Matteo as Ivanovic was a key player for the Blues last season, although he missed the UEFA Champions League final victory over Bayern Munich due to suspension.