Barcelona are looking to reinforce their formidable attack in the January transfer window, Luis Enrique said.

Barça have one of the most potent forward lines in the world in Fifa Ballon d’Or winner Lionel Messi, Neymar and Luis Suárez but lack a reliable replacement if any of the prolific South Americans are sidelined.

Academy graduates Munir el Haddadi and Sandro Ramírez are the only other recognised forwards in the squad but have failed to impress since their promotion from the B team.

“Right now our greatest need is to strengthen the attacking line but I would like bring in reinforcements across the board,” Luis Enrique said. “Negotiations are tough in the winter market because nobody wants to let important players go,” added the former Barça and Spain midfielder. “We will try right up until the final day.”

One option for Barça could be bringing back the former Manchester City winger Denis Suárez. A jewel in Celta Vigo’s youth ranks, Suárez was chased by a number of top European clubs before he decided to join City in 2011 aged 17.

Opportunities for young players were slim and after a couple of seasons in which he made only a handful of first-team appearances he signed for Barça. The 22-year-old performed well on loan at Sevilla in 2014-15 and has become an integral part of a Villarreal side who are riding high in fourth in La Liga.

Barça take a 4-1 lead over Espanyol into Wednesday’s Copa del Rey second leg. Recent meetings have been brutal affairs and Luis Enrique and his Espanyol counterpart Constantin Galca have urged the players and fans to focus on playing football.

Luis Suárez is banned for the game at Cornellà-El Prat after he became involved in a fracas after the end of last week’s first leg at Camp Nou, during which Espanyol had two players sent off.

Luis Enrique said: “We need to approach the match as if it was a single game and not a two-leg tie. Playing Espanyol is always stimulating.”