Barcelona coach Xavi Hernandez said Saturday it was key for his side to replace the departing Sergio Busquets if they want to compete for silverware next season.
The 34-year-old pivot is leaving at the end of the season after making over 700 appearances for the club, winning three Champions Leagues and nine La Liga titles.
"We have to find this piece, if we want to compete well next year, we have to find it," Xavi told reporters ahead of Busquets' final home game, on Sunday against Real Mallorca in La Liga.
"For me it's fundamental as a coach. Busquets has been fundamental for us, and very important in winning the Spanish Super Cup and La Liga this year.
"A player who has been so important for us, on and off the pitch, is leaving, so we have to find a very important player to replace Busquets.
"For me, it's the key to competing next year."
Barcelona have been linked with several players, including Real Sociedad midfielder Martin Zubimendi, but the Catalans are still struggling financially and may be limited to cheaper options.
Along with Busquets, Jordi Alba is also leaving the club in the summer, and fans have sold out the clash with Mallorca to give them a warm farewell, as well as the stadium itself.
Sunday's match is the last to take place at Camp Nou before it is rebuilt, with Barcelona set to play in the city's Olympic stadium in Montjuic next season.
"Tomorrow (we are) saying goodbye to Camp Nou, which is a lot of years of history, passion, emotions, great games, it will be an emotional day," continued Xavi.
"Add to that Busquets and Alba's goodbye, and it's extra motivation for us to play a great game, to show our best, for fans to come to the stadium and have an excellent goodbye."
Xavi said his favourite Camp Nou memory was his own goodbye, in 2015, after the team won the treble, and that it would be sad to play at the stadium in its current guise for the last time.
"It's going to be emotional, with some sadness, we say goodbye to our stadium," added the coach.
"It's for a good cause, the common good of Barcelona -- that said, it will be a bit sad."
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