The 19-year-old is understood to be in London for a medical ahead of a £4.5million switch to Stamford Bridge from Atletico Paranaense.
Nathan, an attacking midfielder, sparked interest from a number of European clubs following an impressive display at the 2013 Under-17 World Cup in the United Arab Emirates.
The transfer, however, would be subject to Home Office approval on a work permit for the Under-20 international, as Chelsea aim to add Nathan to fellow Brazilians Willian, Ramires, Filipe Luis and Oscar in their squad
Chelsea may decide to send Nathan out on loan to gain some valuable first-team experience.
Another player to do just that is striker Patrick Bamford.
The 21-year-old's 17 goals have helped Middlesbrough mount a promotion challenge from the Sky Bet Championship and is reported to be in talks over a new deal at Stamford Bridge.
Chelsea head into this weekend's fixtures looking to move a step closer to the Barclays Premier League title when they host third-placed Manchester United on Sunday.
Striker Diego Costa continues to recover from a hamstring injury, but Loic Remy was expected to shake off the muscle injury which forced him out of the win at QPR, where veteran forward Didier Drogba led the Blues attack
Source : PA
Source: PA