Arne Slot has told Amara Nallo his sending off against PSV is "a big moment to learn from" after the teenage defender was shown a red card on his Liverpool debut.

Nallo, 18, came off the bench in the 83rd minute of Liverpool's 3-2 defeat in the Netherlands on Wednesday. Yet he left the field just four minutes later after being shown a straight red card for fouling PSV forward Johan Bakayoko while he was clean through on goal.

Slot was asked about Nallo's dismissal after the game and urged the youngster to learn from his mistake. "It is cruel but he has never played first team football before and to make your debut in the Champions League is probably the hardest," Slot told TNT Sports.

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The Reds took the lead in the 28th minute after Cody Gakpo scored from the spot. Bakayoko equalized for PSV before Harvey Elliott restored Liverpool's advantage. Yet goals from Ismael Saibari and Ricardo Pepi just before halftime turned the game on its head.

Liverpool was unable to recover during the second half. Nallo allowed Bakayoko to get in behind the defense and had no choice but to make a late challenge. Slot added on Nallo: "He misinterpreted the situation and it's a big moment to learn from.

"It is cruel when you think I'm making my Champions League debut but you go off a few minutes later. A career isn't always positive, it also has negatives and he has to make sure he plays in this competition again."

Liverpool had already confirmed its place in the last 16 of the Champions League, allowing Slot to rest several first-team players. Caoimhin Kelleher, Jarell Quansah, Wataru Endo, James McConnell, Jayden Danns, Tyler Morton, Trey Nyoni, and Federico Chiesa were among those to get an opportunity to impress against PSV. "It was an eventful game with many games and I think everyone expected that before the game," Slot added.

The Reds boss was also asked about the impressive performances of Chiesa and McConnell during his interview with TNT. On Chiesa, he said: "It has been seven, eight, nine months ago, maybe longer and it was important that he got the chance to play 90 minutes. It was important also that he could compete for 90 minutes, he was always sprinting and doing his work."

On McConnell, Slot continued: "If I had been surprised that would mean he had not been at this level in training, but he has been competitive. I'm not surprised but you always wonder how they will react on this stage at this level. James deserves credit for his performance today."