UEFA.com's Paris Saint-Germain correspondent Chris Burke and FC Barcelona reporter Graham Hunter discuss where the quarter-final will be won and lost.
Article top media content
Chris Burke: Paris Saint-Germain may have to wait for the quarter-final second leg to display their usual strengths, with talisman Zlatan Ibrahimović and Marco Verratti suspended for the first game and Thiago Motta currently sidelined from one of Europe's best-balanced midfields. Blaise Matuidi will nonetheless bring his bustling qualities to bear. The French champions also proved they can thrive in adversity when battling to victory at Chelsea FC.
Graham Hunter: Under Luis Enrique FC Barcelona now defend better – and as a team. Their famous 'pressing' is restored and high level. The coach's main reboot of the Barça formula, however, brings into play a potentially lethal asset – the speed, technique and innate understanding of Lionel Messi, Luis Suárez and Neymar.
Chris Burke: Player absences could hit Paris hard, with Ibrahimović's one-match ban placing much attacking responsibility on the shoulders of out-of-form Edinson Cavani. Centre-back David Luiz is another missing link and his injury will force a rejig, with Marquinhos likely to be brought back into the middle and Gregory van der Wiel taking over at right-back, where his defensive capacities are not always convincing.
Graham Hunter: Interestingly, it was Paris who first provided evidence of specific Barcelona weaknesses. Despite a splendid first season at Camp Nou, Marc-André ter Stegen has occasionally shown there is work to do on crosses into the box. Paris scored twice from that route in the clubs' first group game.
Chris Burke: Laurent Blanc's men have lost just once in 18 matches since 10 January, a run which lifted them top of Ligue 1 at the end of March. On the continental stage, Paris are unbeaten in 33 home games and, of course, have already faced Barcelona this term, winning 3-2 at home before going down 3-1 away in the group phase.
Graham Hunter: Even by Barcelona's standards, 2015 has been exceptional. There is patent unity, enjoyment of the playing style, cohesion and, during that time, a series of very big victories over major rivals like Club Atlético de Madrid, Real Madrid CF and Manchester City FC. Goals have been scored freely.
Chris Burke: Paris have excelled in knockout contests this campaign and will go into the opening leg fresh from tackling SC Bastia in the French League Cup final. They also take on AS Saint-Étienne in the French Cup semi-finals tonight, though their real hope is to avoid a third consecutive UEFA Champions League last-eight exit. In fact, they have reached the semi-finals just once before, in 1994/95.
Graham Hunter: Knockout pedigree is something the majority of the Barcelona squad have specialised in down the years. Almost every player has been to the final or finals of the UEFA European Championship, FIFA World Cup, FIFA Club World Cup, FIFA Confederations Cup, Copa del Rey and, of course, the UEFA Champions League or UEFA Europa League. That know-how helps at the most tense moments of knockout ties when errors can be fatal.
Chris Burke: The Ligue 1 title holders showed they can beat Barça without Ibrahimović back in September and proved they can eliminate a European giant against Chelsea, yet they needed their centre-backs to get the goals at Stamford Bridge. Looking at the attacking riches at Luis Enrique's disposal, it is hard to escape the feeling Paris will fall short up front.
Graham Hunter: It is difficult not to see Barcelona profiting from Paris's player absences and drawing the first leg, before imposing their notable strength at the Camp Nou to advance.
One to watch
Chris Burke: With Verratti and Motta out of the 15 April opener, Paris could require Javier Pastore to operate at his craftiest best. The Argentina playmaker is an exquisite passer and mover of the ball and has restated his credentials this term after fading from view before the current campaign.
Graham Hunter: Suárez might seem an obvious choice given his fantastic scoring ability but his stated goal, above all others, is to win the UEFA Champions League. A driven man.
Possible starting XI
Paris: Sirigu; Van der Wiel, Thiago Silva, Marquinhos, Maxwell; Pastore, Cabaye, Matuidi; Lucas, Cavani, Lavezzi.
Barcelona: Ter Stegen; Alves, Piqué, Mascherano, Alba; Rakitic, Busquets, Iniesta; Messi, Suárez, Neymar.