Patrick Roberts scored against his parent club as Manchester City's Champions League group campaign ended in a 1-1 draw with Celtic.
The final positions had already been decided in Group C, with City qualifying second behind Barcelona and Celtic finishing bottom.
City manager Pep Guardiola will, however, have been keen to bounce back from Saturday's 3-1 Premier League defeat to Chelsea and a 3-3 draw in Glasgow earlier in the season that started a six-game winless run in all competitions for his side.
But it was one of City's own who put Guardiola's men on the back foot inside four minutes at the Etihad Stadium, Roberts - on an 18-month loan at Celtic - capping a determined run with a powerful finish.
Another City youngster – this time wearing the blue of the hosts – soon levelled, Kelechi Iheanacho rounding off a swift counter-attacking move.
The pace of the game started to reflect its dead-rubber status as it wore on and Nolito's rightly-disallowed goal was as close as either side came to snatching a winner in the second half.
That ball was pounced on by Moussa Dembele – scorer of two goals in the reverse fixture – before Tom Rogic forced a retreating Willy Caballero into an early save.
Celtic's lead was short-lived, Iheanacho powering a strike past Craig Gordon four minutes later after getting on the end of a precise Nolito throughball.
It was City who looked most likely to edge in front before the break - Erik Sviatchenko turned behind a dangerous Nolito ball into the six-yard box, before Gordon got down well to keep out a clever Iheanacho flick.
Celtic replacements Leigh Griffiths and Gary Mackay-Steven both went close for the visitors late on - the former sweeping wide from the edge of the box, before his team-mate was denied by a strong Caballero hand.
