The Argentine has cut his holiday short to return to work with the treble winners, with his compatriot Javier Mascherano doing the same.
Lionel Messi and Javier Mascherano have reported back early for pre-season duty with Barcelona.
The duo were not due to return to Catalunya until Monday after participating at the Copa America in Chile earlier this summer, but both have now joined their team-mates four days early.
The four South Americans were accompanied by Marc-Andre ter Stegen for Thursday’s medical examinations. The German goalkeeper, who played at the European Under-21 Championship, did go on the US Tour, but had yet to take the routine medical checks.
The return of Messi, Mascherano, Neymar and Dani Alves means Luis Enrique now nearly has his full squad at his availability again.
Chile international Claudio Bravo is still away on holiday and will be joining his team-mates on Monday.