Louis Smith criticised the judges after finishing second behind his Hungarian rival Krisztian Berki in the pommel horse final at the European Gymnastics.
Beijing 2008 bronze medallist Smith posted a score of 15.775 only for Berki to come up with 15.958 moments later.
Afterwards, Smith suggested judges had given Berki an artificially high start score - which gauges the difficulty of the gymnast's routine.
He tweeted: "Berki's start score was wrong and I should have won."
The start value plays an important part in determining a gymnast's eventual score. Smith and Berki were both given start values of 6.9, meaning the gold medal came down to the execution score, where Berki outscored Smith by 0.183 marks.
But Smith believes Berki received 0.2 marks more than he deserved for the difficulty of his routine. Had that 0.2 been taken away, Smith would have won European gold for the first time.
Smith told BBC Sport: "If it had been a 6.7, I would have been in front. When you're in second and you get told maybe you should be in first because the start scores are wrong, it's annoying.
"I should have won today. I didn't do anything special or out of the ordinary, I just did what I had to do.
"It's tricky - I've got to stay cool and do my thing [to beat Berki at the Olympics]. Hopefully I can do the job."
Berki, 27, has also beaten 23-year-old Smith to the past two world titles, with Smith finishing second in 2010 and third behind France's Cyril Tommasone in 2011.
For Smith, his hopes of winning Olympic gold this summer may depend on whether he can find a way past the Hungarian.
That will again involve difficulty scores. If Smith can improve his own start value - he is believed to be preparing one or two of the sport's hardest manoeuvres - then Berki may yet be threatened at London 2012. The challenge will be in executing those tricky moves cleanly, or else the benefit is lost.
Despite Smith's silver medal, this week's biggest development remains the performance of GB's five men on Saturday in lifting their first European team title, beating traditional powerhouse Russia.
That result was the best in the history of British gymnastics, with neither the men nor women having ever achieved first place at European or world level previously, and is an important pre-Olympic marker.
Ahead of the individual finals and with that title in the bag, the decision was taken to rest Dan Purvis, who had been ill earlier in the week.
He did not take part in Sunday's floor final despite qualifying. Kristian Thomas initially finished fourth but was downgraded to fifth as France's Gael da Silva moved up to bronze on appeal.
Ruslan Panteleymonov came sixth in the vault final with Thomas eighth, while Max Whitlock produced an entertaining but slightly wild routine in the pommel horse final for sixth place.
Team gold here came six months after a concerning display at the 2011 World Championships in Tokyo, where the GB men finished 10th in qualifying and missed their first chance to qualify for London 2012.
They came through at the second opportunity, during January's Olympic test event inside London's O2 Arena, and Britain will send the maximum number of gymnasts - two teams of five, plus reserves - to the Games.
Meanwhile, Britain's juniors completed a remarkable European Championships with three individual gold medals on Sunday.
Frank Baines (high bar), Courtney Tulloch (Britain's first rings medal at any level for a decade) and Jay Thompson (pommel horse) picked up gold, following all-around gold for Baines on Friday and junior team gold on Wednesday.
The GB juniors won five of the eight junior titles available in Montpellier, suggesting the new era in British gymnastics heralded by senior results here may continue for some years.