The first leg ended 2-2 in Paris thanks to Blaise Matuidi’s last minute strike for the hosts but the biggest blow for Barca was the injuries suffered by Messi and Javier Mascherano.
Four-time world player of the year Messi still has a chance of returning for tonight’s clash at the Camp Nou but Mascherano’s knee injury will see him miss the majority of what remains of the season.
But Xavi said that two away goals and home advantage should still be enough to see Barca into their sixth consecutive semi-final.
“We have 90 minutes left at home and we will play in front of our fans, who showed the top level of devotion in the game against Milan,” he was quoted as saying in an interview on uefa.com published on Monday.
“The shame has been the injuries, Mascherano’s just as much as Leo’s. We are going to see how Leo is, Mascherano it seems will miss four to six weeks and they are important absences. But we have a good result, we are favourites, playing at home and there are 90 minutes to play.”
The tie promises to be another special night at the Camp Nou after Barca produced a stunning comeback to reverse a 2-0 first-leg deficit to beat AC Milan 4-2 on aggregate in the last round.
Xavi pinpointed that match as a key moment in the Catalans’ season as they target a third Champions League triumph in five years.
The loss of Mascherano only compounded an already tricky situation for Barca at the back with captain Carles Puyol and Adriano also injured, whilst Eric Abidal has just returned from 14 months out of action after undergoing a liver transplant.
Cesc Fabregas is likely to start should Messi not be fit after scoring the first hat-trick of his career at the weekend, whilst Pedro will return after missing the last three games through injury.
PSG meanwhile have defensive concerns with captain Thiago Silva having missed Saturday’s 2-0 win over Rennes due to a knee injury. However, he will travel with the squad along with Thiago Motta who hasn’t played due to an abductor problem. Matuidi is suspended so Marco Veratti seems set to regain his place in midfield.
In pictures: Bend it like Mumbai yogini Natasha Noel
Photos: Varun, Taapsee, Jacqueline promote 'Judwaa 2' on 'Dance Plus 3'
Instagram's newest sensation: Check out these photos of Bruna Abdullah
Photos: This is how Chitrangda Singh looks without make-up
Photos: Malaika Arora parties wearing see-through lace dress