Neymar wasted a couple of openings to edge the hosts ahead early on, firstly failing to control Luis Suarez's pass into the box before heading straight into the hands of Sergio Alvarez from close range minutes later.
The Brazilian forward was involved again shortly after when his curling effort from range came back off the crossbar, as Barca continued to probe for an opening goal.
Lionel Messi, closing in on becoming La Liga's record goalscorer, was denied by Alvarez after being picked out by Neymar, shortly before driving into the Celta box and striking the crossbar with a deflected effort.
Barcelona saw two more chances come and go before the interval, with Messi heading over a decent Suarez cross into the box, while the former Liverpool man could not get the better of Alvarez at the end of his run.
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