The Italian coach has told his side they cannot afford to focus on their former striker alone, but warned the Portugal star is fired up following his domestic suspension
Former Blancos forward Huntelaar is set to make his first appearance in this season's competition in the last-16, first-leg tie in Gelsenkirchen, while Ronaldo is also set to start after sitting out last weekend's Primera Division meeting with Elche, the final game of his three-match ban in La Liga.
While the pre-match focus has been primarily on the duel between the attacking duo, Ancelotti has warned his side against focusing solely on nullifying Huntelaar.
"Ronaldo is especially motivated because he wants to play. He wasn't happy with the sanction. He has trained very well during this time," Ancelotti told a press conference.
"Ronaldo's condition is optimal for tomorrow [Wednesday].
"I don't think it's an individual duel between Ronaldo and Huntelaar. Huntelaar is a very good striker, a very good player across the attack, we have to be careful with him. But the match is between Madrid and Schalke.
"Schalke have a very well-organised defence, with very good young players like [Max] Meyer and [Julian] Draxler and others with experience like Huntelaar and [Kevin-Prince] Boateng.
"They play concrete football, not spectacular, but solid, with good organisation. They play very well together, they have quality.
"It will be a game with a lot of intensity. Schalke will try to do everything to win, that's clear. We will have to give everything."
Ancelotti, who confirmed Gareth Bale is also set to start the match, admitted he is eager for his side to find the missing ingredient in their Champions League endeavours, after being knocked out at the semi-final stage for three consecutive seasons.
"Nothing changes," the Italian argued. "I'm here to do my very best in all competitions. Everyone knows the Champions League is the most important competition in the world.
"Reaching the semi-finals three times is special, the work was good, but we missed something, I don't know what."