Juventus virtually sealed its place in the quarterfinals of the Champions League on Tuesday, punishing poor defending with some clinical finishing to beat Celtic 3-0 in their last-16 first leg.
Mistakes by defender Efe Ambrose, who only returned from international duty at the African Nations Cup on the morning of the match, led to goals by Alessandro Matri in the third minute and Mirko Vucinic in the 83rd.
Claudio Marchisio had scored the second goal in the 77th at the end of a flowing team move by the Italian champions and current Serie A leaders, who inflicted Celtic's joint-heaviest home loss in European competition.
The score line was harsh on Celtic, which dominated the first half and most of the second, only to lack a cutting edge to beat Juventus goalkeeper Gianluigi Buffon.
"We need a miracle but it's the harsh reality of Champions League football," Celtic manager Neil Lennon said.
The second leg is in Turin on March 6, when Juventus will look to finish the Scottish champions off and maintain its unbeaten run in this season's competition. Antonio Conte's side will know it rode its luck in Glasgow, though.
Celtic showed by beating Barcelona in the group stage that the team is a match for anyone at its intimidating Celtic Park home, and it posed Juventus all sorts of problems with its relentless work rate and high pressing game.
Even Italy midfielder Andrea Pirlo, usually so composed and elegant in centre midfield, was clearly ruffled at being hustled and harried but Celtic couldn't find the finish to go with its build-up play.
"The score line flatters Juventus," Lennon said. "For 70-odd minutes, we were by far the better side but you can't give away sloppy goals."
Lennon may be regretting playing Ambrose on the day he landed in Scotland after more than a month away with Nigeria at the African Nations Cup. He played in the 1-0 victory over Burkino Faso in the final on Sunday but was rushed back for the biggest game in Celtic's recent history.
"We took a gamble on Efe Ambrose," Lennon acknowledged.
For the opener, Ambrose misjudged a routine ball forward to leave Matri clean though on goal. The striker poked a finish through goalkeeper Fraser Forster's legs and the ball crossed the line by the time Kelvin Wilson slid in to clear away.
Marchisio slammed the loose ball into the net for good measure — with the assistant referee yet to signal — but Matri was given the goal.
Ambrose then pondered too long on the ball before being robbed by Marchisio and he fed Vucinic, who slipped a low finish into the net. Ambrose hung his head in despair.
Celtic's response to conceding early had been very impressive, peppering Buffon's goal with shots throughout the first half. Kris Commons had a handful of chances while Victor Wanyama headed over from a corner just before halftime, which Juve would have been relieved to reach without conceding.
The decibel levels remained high for the second half, as did Celtic's dominance — but still Buffon's goal wasn't breached.
Commons skied a shot over before Ambrose headed a golden chance straight at Buffon when completely unmarked eight yards out.
Marchisio punished Celtic for its profligacy by adding the second goal, running onto Matri's slick through-ball, cutting inside and firing in a shot that Forster couldn't keep out.
Goals by Ezequiel Lavezzi and Javier Pastore gave Paris Saint-Germain an important 2-1 away win at Valencia in a the first leg of their Champions League last-16 match Tuesday, which still ended badly for the French team as it allowed a late goal and had star striker Zlatan Ibrahimovic needlessly sent off in injury time.
PSG looked to have virtually secured a spot in the quarterfinals after Lavezzi hit his fourth goal of the season with a fierce strike in the 10th minute and Pastore doubled the lead in the 43rd when he shot through Valencia goalkeeper Vicente Guaita's legs.
But Valencia breathed life into the series when Adil Rami latched on to a perfectly delivered free kick by Tino Costa in the 90th, and Ibrahimovic then earned a straight red card for a clumsy challenge on Andres Guardado, meaning he will miss the return leg.
Up until those final few minutes, everything had worked perfectly for PSG, which is trying to establish itself as a European power after spending lavishly on star players since being bought up by wealthy Qatari owners.
While Valencia was allowed to control play for much of the game — enjoying more than 60 per cent of possession — the French team calmly sat back and defended, before launching counterattacks that always proved dangerous.
PSG's 20-year-old attacking midfielder Lucas Moura was behind many of those counterattacks in the first half, wreaking havoc with his speed along the right wing and possible leaving new signing David Beckham — who watched on in the stands — wondering where he can find a spot in the lineup.
Moura hit the post with a fierce strike from distance in the ninth minute, but PSG still went ahead moments later.
Lavezzi played a one-two with Pastore and then skillfully dribbled past defender Ricardo Costa into the area before sending a fierce shot past Guaita, who allowed the ball to pass over his shoulder.
Valencia midfielder Ever Banega had a chance to equalize when he pounced on a poor clearance but shot wide in the 20th.
Moura was then behind PSG's second goal, breaking down the right flank and going past a defender before squaring the ball for Pastore, whose low shot snuck past Guaita, who again looked like he had a chance to save it.
Moura was then taken off early in the second half with an apparent ankle problem, but PSG still created several chances to extend its lead.
Ibrahimovic and Lavezzo both had efforts saved, while substitute Clement Chantome had a goal ruled out for offside — despite protests from the French team that a Valencia player had last touched the ball.
Valencia also had chances, with Nelson Valdes wasting the best one when he received a lobbed pass in the area but shot into the side netting in the 76th.
But the Spanish team finally broke through when Costa's free kick sailed over the PSG defence and Rami was there to knock it into the net. And Valencia's chances of turning things around then increased significantly when Ibrahimovic — possibly frustrated at conceding a goal — stamped Guardado's foot in a reckless challenge near Valencia's corner flag, leaving the French team without its top player for the return game.