Paris Saint-Germain boss Unai Emery faces a major dilemma regarding his back-line to face Barcelona on Tuesday night (14 February) after Thiago Silva failed to make the 18-man squad due to an injury. Thiago Motta is also ruled out through suspension, but the Spanish boss has recovered Javier Pastore ahead of the first leg of the Champions League last 16 clash, to be played at Parc des Princes.

Silva, 32, missed Friday's league victory over Bordeaux due to a muscle injury but was expected to return to action against Barcelona, in order to help his side to stop the "MSN" trident formed by Lionel Messi, Luis Suarez and Neymar.

On Monday, Emery suggested that his only injury concern for the visit of the La Liga champions was Pastore.

"We will see how training goes on Monday afternoon, but everyone is feeling good," Emery said in a press conference after Marco Verratti, Kevin Trapp and Thomas Meunier returned from injury in the victory over Bordeaux.

"Pastore? He is a lot better and trained with the squad this weekend, and he will train with us today. He needs to get his match fitness up to play a full 90 minutes. He is a quality player and can bring a lot to the team. We will decide today if he will be in the squad for Tuesday's match."

But the captain sat out the training session on Monday evening and was consequently left out of the 18-man squad to face Barcelona. The news is a major blow for Emery as he will also be without Motta due to suspension.

Adrien Rabiot, Blaise Matuidi and Verratti are ready to form the midfield against Barcelona in Motta's absence, but the former Sevilla boss faces a headache to find a partner for Marquinhos to replace Silva. Presnel Kimpembe is the natural choice but the 21-year-old is yet to make an appearance in the Champions League and Emery could consider to use instead a more experienced option to stop Messi and co in the shape of right-back Serge Aurier.

Elsewhere, the positive news for the PSG boss was the return of Pastore, although the Argentine star will surely start the game against Barcelona on the bench. Edinson Cavani has a fixed place as the number nine while Angel Di Maria, Lucas Moura and January signing Julian Draxler are expected fight for the other two spots in attack.