The African nation appeared to have rescued a point in Natal on Monday when Andre Ayew cancelled out Clint Dempsey's first-minute opener in the closing stages, only for American defender John Brooks to head a dramatic winner.
Ghanaian news website Joy Online reported a scheduled Tuesday press conference was cancelled amid player unrest, naming experienced midfielders Sulley Muntari and Kevin-Prince Boateng among a group of players unhappy with the tactics employed by Appiah during the 2-1 Group G reverse.
Schalke's Boateng only featured as a 59th-minute substitute and Joy Online said: "Kevin is on record to have criticised the tactics by the coach. He said he was surprised he was kept on the bench when he should have started."
They tweeted: "@ghanafaofficial rejects as false, reports by Joy Fm, Graphic & Citi FM claiming there is player revolt after the defeat to #USA.
"@ghanafaofficial all players have turned up for training and (are) poised to face #GER (Germany). They are focused on #FifaWorldCup."
