The world record signing has missed Real's last two matches with the problem after pulling up in the warm-up ahead of the 4-1 victory over Getafe, but he returned to training on Thursday.
Bale rejoins a squad that will be full of confidence following their controversial victory over Elche on Wednesday, although they will likely still have the words of coach Carlo Ancelotti ringing in their ears.
Ancelotti's side needed a highly debatable last-gasp penalty from Cristiano Ronaldo to secure the points with the last kick of the game in midweek, and the Italian admitted that his players must do more if they are to overcome their arch-rivals at the Bernabeu this weekend.
"Playing the way we did (against Elche), we are not going to win the derby," he said. "We need to play better, with more intensity and more personality."
Atletico made it six wins out of six with their 2-1 win over Osasuna on Tuesday and they will be hoping to maintain their perfect record in the first derby of the season.
They won their last meeting with Real in extra time in last season's Copa del Rey final but they have not tasted league success against their capital counterparts since 1999.
Coach Diego Simeone will be hoping to break that run of 23 league games without a win and they will be brimming with confidence after their perfect start to the Liga campaign.
Goalkeeper Thibaut Courtois believes they have what it takes to extend that run, and has reassured the fans that they are going all out for the win.
"We have a great team," he said. "We know how to beat them.
"As a player you never play to draw, always to win."
Real are also unbeaten in the league, but they did drop points in a 2-2 draw with Villarreal that leaves them two points behind their city neighbours and champions Barcelona.
They will need to stop striker Diego Costa if they are to take all three points on Saturday, with the 24-year-old Brazilian having netted his sixth and seventh goals of the season in the midweek win.
Xabi Alonso is definitely out for the hosts with a foot injury, while Adrian will be missing for the visitors with a fractured cheekbone.
