Paulinho was injured in Barcelona's loss to Espanyol in the first leg of the Copa del Rey quarterfinals.
Barcelona midfielder Paulinho is reportedly facing the prospect of a month on the sidelines after suffering a foot injury in the club's defeat to Espanyol in the Copa del Rey quarter-final on Wednesday night.
The Brazilian was substituted just eight minutes into the second half proceedings at Cornella-El Prat after he signalled to the club's bench that he was not fit to continue.
The 29-year-old will undergo a series of tests and scans with the club's medical team on Thursday which will determine the extent of the injury, with a fracture to his fifth metatarsal in his right foot considered to be the worst case scenario - as per AS.
If tests confirm a fracture, it will ensure Paulinho faces up to a month on the sidelines, with the final results set to be received by no later than Thursday.
The 29-year-old was a surprise target for Barcelona throughout the summer, but his return of eight goals in 24 appearances across all competitions has somewhat quieted his critics who have made note of his journey from Tottenham, to Guangzhou Evergrande in the Chinese Super League and now Camp Nou.
Barcelona's defeat at the hands of Espanyol was the club's first since the Spanish Super Cup this season and although the frustrating game ended his side's unbeaten streak, manager Ernesto Valverde remained optimistic that the second-leg will see the club's fans drive the team to victory.
He told AS: "The team that are ahead [going into the second leg] are the favorites. When we drew in Vigo, we were slight favorites. Now the result doesn't favor us. This is the cup, and we have to keep going right to the last.
"It's the cup, and we hope they help us. Their [Espanyol's] fans drove them on today, and I hope ours do the same."