Coach Jens Keller and his relatively inexperienced players admitted that they had no answer to Real Madrid's ruthlessness on the counter-attack in the Round of 16 first leg encounter.
"It's hard to defend when you can't get near the ball. Losing by this much is hard, but deserved," captain Benedikt Hoewedes told reporters after witnessing Karim Benzema, Cristiano Ronaldo and Gareth Bale each score two goals apiece.
"We started well, but you reach a point when you realise 'this is going to be tough'.
"It's a dream to play Real Madrid but a bitter pill to swallow when you're so outclassed. Cristiano Ronaldo was everywhere. We saw today exactly why he's the World Footballer of the Year."
Kevin-Prince Boateng said that Schalke had "reached their limits" while midfielder Julian Draxler added: "We battled as much as we could, but always seemed to be a yard behind our opponents."
BRUTALLY HONEST
Yet Schalke, fourth in the Bundesliga, had won five and drawn two of their last seven league games and believed before the tie that they could give the nine-times European champions a run for their money.
Keller was brutally honest about his team's performance when he was interviewed on ZDF television by a two-man team including former Bayern Munich and Germany goalkeeper Oliver Kahn.
Coaches of German teams in matches televised by ZDF spend around 10 minutes in the studio during which they have the often painful job of analysing key moments in the game before hearing from the usually outspoken Kahn where they got it wrong.
Keller pointed out how several of his players backed off and allowed Bale to rampage through their midfield unimpeded in the run-up to the first goal, while the second followed what he described as a "huge mistake" by defender Felipe Santana.
At that point, the presenter eased Keller's pain by cutting out Real's four second-half goals, instead going straight to Klass-Jan Huntelaar's stoppage time volley consolation strike.
"We have a young team who have a lot to learn, they have to concentrate much more," Keller said. "I hope that we can draw the right lessons from this.
"They wanted to keep going forward but we should have stayed deeper."
Schalke's lineup for the game included Joel Matip (22) and Sead Kolasinac (20), with Draxler (20) and Max Meyer (18) in midfield.
Kahn suggested that teams such as Leverkusen and Schalke should not try to compete on equal terms when facing Europe's elite sides.
"There's a huge gap in quality, so you have to look for other means, other possibilities," he said, implying that spoiling tactics might work better.
Schalke have only three days to pick themselves up before a visit to Bayern Munich, who won 4-0 in Gelsenkirchen earlier this season.
"Despite this heavy defeat, we will not break," promised Keller. "Our team has character, we have shown that in the past few weeks."
(Reporting by Brian Homewood; Editing by John O'Brien)
