The Italian watched his side book their place in the quarterfinals of the Champions League on Tuesday ahead of facing Barcelona in what could be a decisive league encounter.
It was a night of mixed emotions for the capital outfit after Jese Rodriguez was stretchered off with a cruciate knee ligament injury, while Cristiano Ronaldo equalled Ferenc Puskas' record of 242 goals for the club.
Ronaldo opened the scoring early in the first half before Schalke briefly levelled through Tim Hoogland. The Portuguese restored Madrid's lead on 74 minutes and Alvaro Morata rounded off the win 60 seconds later.
"I think we are in a good moment and we are really excited," said Ancelotti after the game. "Europe's best teams have qualified so it will be very complicated for everyone. It is good for Spanish football to have three teams still in the competition."
However, Ancelotti admitted the atmosphere in the dressing room was a subdued one following the news of Jese's knee injury, which looks set to rule the 21-year-old out of action for several months.
"I believe Jese Rodriguez has broken his cruciate knee ligament. He is really unlucky," the Italian added. "We will lose a very important player who has played very well this season but that is football. The dressing room has been affected by his injury."
Madrid's focus will now turn to La Liga and Saturday's Clasico encounter with Barcelona on Sunday evening. Victory for Ancelotti's side will put the Liga leader seven points clear of its arch rivals and the 54-year-old reveals he already knows which players will feature at the Bernabeu.
"We have to give our absolute best to beat Barcelona. I know which lineup I will use, it is not difficult and I won't complicate things."