The Catalan giants continue their search for a new left-back as a long-term successor to Eric Abidal and are closely monitoring the Schalke and Granada players
The Catalans are in the market for a new left-back due to the uncertainty surrounding the future of Eric Abidal, who is due to undergo a liver transplant in the upcoming weeks.
Valencia star Jordi Alba remains the Blaugrana's first choice, but the club is already weighing up alternatives in the event that they miss out on the Spain international's signature.
The 25-year-old Siqueira impressed against Barcelona in Tuesday's 5-3 loss, and has been a key figure for Granada this term.
The Brazilian defender previously failed to succeed at clubs such as Inter, Lazio and Udinese, but his performances in La Liga have allegedly persuaded Barcelona to monitor his progress.
Meanwhile, Fuchs, 25, has impressed at Schalke since joining the Gelsenkirchen side from Mainz in the summer of 2011, and his attacking style of play has reportedly convinced Barcelona scouts.