Luiz sustained the injury in Sunday’s goalless draw with Arsenal when he clattered into the advertising hoardings at the end of the first half.
The Brazil defender continued in the second half until he was dismissed after 87 minutes for a reckless tackle on Sead Kolasinac which resulted in a three-game suspension.
Luiz missed Wednesday’s 5-1 League Cup win over Nottingham Forest and will also be ineligible for the Premier League clashes with Stoke and table-topping Manchester City.
But Conte, whose side beat Qarabag 6-0 in their opening Group C match in the Champions League, expects Luiz to play at Atletico next Wednesday.
“He must be OK,” Conte said. “David is an important player for us. For sure he will be ready for the game against Atletico Madrid.”
In Luiz’s absence, Chelsea’s youngsters impressed against Championship side Forest.
Michy Batshuayi scored a hat-trick while Kenedy and the impressive Charly Musonda were also on target for Chelsea. Tendayi Darikwa scored a late consolation.
Eden Hazard made his first start of the season after suffering a broken ankle.
Conte suggested he could field a similar squad in the fourth round of the League Cup against Everton.
“We are a great club, for this reason every competition is important to us,” he said. “If we answer like this tonight, why not continue to give the opportunity to these players?”
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