Al Sadd, who lost 2-1 in the first leg, will be without defender Ibrahim Majed for the decisive second leg as he is still recovering from foot surgery.
However, Ammouta will be able to call on midfielder Jasser Yehia, who was suspended for the first leg, while former AFC Player of the Year Khalfan Ibrahim is also likely to play as he has nearly recovered from a hip injury.
"The match against Lekhwiya will be very tough and difficult," Ammouta told the Gulf Times. "We will be playing against a strong team who won the local league.
"We need to maintain our concentration particularly as we have had some big matches recently and the schedule has been heavy for us. Winning the Emir’s Cup will give us a big push and the players will be motivated to get a positive result."
Ammouta also admitted that his side haven't had a lot of time to prepare for the second leg against Lekhwiya due to their hectic schedule.
"There hasn’t been a lot of time between the Emir’s Cup final and the match against Lekhwiya to prepare well," he said. "The weather conditions will also be important, but I’m confident that we will go into the match with great concentration and motivation."