Philippe Coutinho saved Brazil in stoppage time after they struggled to break down Costa Rica, with Tite's side eventually winning 2-0.
After a stodgy first-half showing, Brazil, who drew their opening match with Switzerland, wasted numerous chances before Coutinho (90+1) netted his second goal of the tournament to rescue his side.
Neymar (90+6) added gloss with a further goal in added time.
The PSG man was at the heart of the game throughout, including winning a penalty which was sensationally overturned by VAR and at full time he was in tears, presumably with relief that Brazil had avoided a damaging result.
Cristian Gamboa gave Brazil an early fright with a scorching run down the left.
His cross found Celso Borges but his effort from 12 yards out scuffed wide of the far post.
Gabriel Jesus had the ball in the net on 26 minutes, however, the linesman's flag correctly cut short the celebrations and Neymar cut a frustrated figure off the left flank as Brazil failed to find any rhythm to their play down his side.
But the substitution of Douglas Costa, who replaced Willian at the break, sparked life into Brazil's attacks.
First, Jesus rose highest from a right-wing cross only for his his effort on 50 minutes to come crashing back off the crossbar.
Neymar then swept an effort from 12 yards at goal which was flicked over the crossbar from Keylor Navas who could only stand and watch minutes later when the same player curled an effort inches wide.
The Brazilian skipper was seen badgering the referee in the tunnel over an alleged lack of decisions go his way in the first-half but he thought he'd won a penalty with 12 minutes left.
He cut inside Oscar Duarte, who left an arm on his chest.
Neymar deemed this contact strong enough to send him theatrically to the ground but the VAR overturned the call to the frustration of the Brazilian, who was booked moments later for dissent.
Brazil were running out of ideas and time - but when Roberto Firmino bravely headed a cross back across goal, Jesus flicked the ball into Coutinho's path and the Barcelona man toe-poked the ball through the legs of Navas, sparking jubilant scenes.
Neymar then wrapped up the points late on with a simple finish after a clever break by Costa.
Both these two nations play their final Group E games on Wednesday, with Brazil taking on Serbia and Costa Rica playing Switzerland.