Christian Doidge helped Forest Green win promotion to the English Football League, scoring in the National League promotion final at Wembley last May
Forest Green boss Mark Cooper accused his top scorer Christian Doidge of diving twice in an attempt to win a penalty in their 1-0 defeat at Swindon.
Doidge, who has scored 17 times in 26 appearances for League Two strugglers this term, had two second-half appeals waved away after going down in the box.
"I'm very angry with Christian. He dived twice in the box," Cooper said.
"Nobody is near him and he's chosen to fall on the floor when he had chance to score his 18th and 19th goals."
Referee Dean Whitestone did not caution Doidge after either incident, but his team-mate Reuben Reid was shown a yellow in the 87th minute for his protests following the second appeal.
Luke Norris scored the only goal of the game nine minutes earlier, condemning Forest Green to their sixth defeat in seven league games.
Their loss, coupled with Chesterfield's win over league leaders Luton, saw Cooper's side - who are in their first season in the English Football League - slip into the relegation places.
Meanwhile, Rovers defender Farrend Rawson was taken to the Great Western Hospital to undergo checks after being knocked unconscious in the first half.