The road to Madrid begins this week as the league phase gets under way - but which teams are currently looking in the best shape to go on and lift the European Cup?
Martin O'Neill took full responsibility after Celtic suffered an extraordinary collapse against LASK to crash out of Champions League qualifying. The Scottish giants squandered a commanding 4-0 aggregate lead before falling to a 5-1 second-leg thrashing after extra time, missing out on the league phase for the second consecutive campaign.
Celtic captain Callum McGregor has issued a grovelling apology to supporters after his side threw away a four-goal aggregate lead to crash out of the Champions League against LASK. The Hoops suffered a monumental 5-4 extra-time defeat in Austria and will now drop into the Europa League.
AC Carpi
