Arda Turan, Javier Mascherano and Jérémy Mathieu are reportedly a doubt for the crucial Champions League visit of Juventus on Wednesday night (19 April) after the three Barcelona players could not train with the rest of their available teammates on Sunday.

Mundo Deportivo adds that Gerard Piqué and Sergio Busquets also missed the workout but the two Spanish internationals are expected to be fit ahead of a decisive week which will end with a trip to Real Madrid for the second El Clásico of the campaign.

Turan, 30, was ruled out for around three weeks on 29 March after suffering an injury in his groin while on international duty with Turkey.

The former Atletico Madrid star appeared to be on course to return to action for the Saturday's clash with Real Sociedad, after last week Barcelona informed that he was back in training.

However, he eventually failed to make Luis Enrique's squad for the 3-2 win over the Basque side and Mundo Deportivo reports that he was also a surprising absentee in the Sunday's workout.

It is uncertain whether the Barcelona playmaker has suffered a setback in his recovery but Mundo Deportivo suggests that he could be unavailable to help his side on Wednesday night in their bid to overturn a 3-0 deficit from the first leg in Turin.

Nevertheless, Luis Enrique has given his players the Monday off so the Turk will only have one session to prove his fitness before the decisive Champions League encounter with the Italian side.

Turan was not expected to start against Juventus anyway but the news is a concern for Luis Enrique ahead of the Sunday's visit to Real Madrid as Neymar is ruled out to face Los Blancos due to suspension – and the Turkish international could be one of the candidates to replace him if he is fit.

Pendientes de Masche y misterio con Arda y Mathieu https://t.co/4VusXPYAvf pic.twitter.com/Lx2FgGCNv5 — Mundo Deportivo (@mundodeportivo) 16 de abril de 2017

Meanwhile, Mascherano is also said to be a doubt to face Juventus after the versatile defender suffered an injury in his left calf during the first leg of the Champions League quarter-finals.

Barcelona then suggested that the Argentina only had a minor problem but he was ruled out for the game against Real Sociedad and continued on the sidelines when the rest of his teammates begin the preparations for the crucial encounters with Juventus and Real Madrid.

The delay in Mascherano's recovery is a special concern for Luis Enrique as Mundo Deportivo reports that Mathieu also missed the Sunday's workout despite having been on the bench against Real Sociedad.

The hypothetical absence of the two centre-backs may force Luis Enrique to use a 4-3-3 formation against Juventus rather than a 3-4-3 as he would only have Gerard Pique and Samuel Umtiti available to form the heart of his backline.

In this sense, Mundo Deportivo points out that both Pique and Busquets trained in the gym on Sunday rather than with the rest of their teammates. However, it looks that their absence was only precautionary and the two Spanish internationals should be ready to start against both Juventus and Real Madrid.

Meanwhile, Barcelona informed that Luis Enrique also promoted Carles Aleñá, Marc Cardona, Àlex Carbonell, Ignacio Abeledo and Borja López from the second team to the training session as long-term injury duo Rafinha Alcantara and Aleix Vidal remain on the sidelines.