Spinner Usman Qadir and Sam Whiteman make way for Marsh and Kelly.
Coach Adam Voges said his side were looking forward to a string of home games after a tricky start to their campaign.
“We’ve got our next five out of six games at Optus, so the likes of Matt Kelly become an attractive option given its fast bowler friendly,” Voges said.
“It’s great to have Mitch back in the side, his experience and leadership is always first class.
“Of course it is very exciting to be back at home, we had some great support on boxing day and hopefully the fans will come out again and continue to support us.”
“We haven’t had the start to the season we were hoping for, but the boys are working hard and we know that we can turn things around quickly especially in this form of the game.”
The Scorchers host the Brisbane Heat at Optus Stadium tomorrow night.
GAME DETAILSKFC Big Bash League – Game 6
Perth Scorchers v Brisbane Heat
Saturday 5 Jan @ Optus Stadium
Broadcast: Fox Cricket @ 6:30pm AWST