The AC Milan defender missed his side's session again on Saturday yet the club's doctors are still optimistic the player will be fit for Sunday's quarter-final
The AC Milan centre-back has not trained since Thursday due to the injury and is running out of time to get the all clear for Sunday's game.
However, one of the Brazilian team's doctors, Rodrigo Lasmar, is optimistic the 26-year-old could play versus Paraguay, despite his lack of training.
"Thiago Silva has been with the physios, doing specific training in the pool. We better save him becaue it would be an unnecessary risk to put him on the field today [Saturday]. But he has made a very good improvement and is likely to play on Sunday," Lasmar told Brazilian press.
Thiago Silva has played every minute of Brazil's Copa America campaign so far, helping the nation finish top of Group B.
If the Milan defender is unable to regain his fitness for Sunday's crunch encounter, David Luiz is likely to step in at the centre of defence to partner captain Lucio.