* Two athletes test positive for drugs at Sochi Olympics
* German and Italian thrown out of Olympics
* Only one athlete caught at 2010 Vancouver Games
By Karolos Grohmann
SOCHI, Russia, Feb 21 (Reuters) - Germany's two-time Olympic cross-country skiing champion Evi Sachenbacher-Stehle and Italian four-man bobsleigh member William Frullani were thrown out of the Sochi Olympics on Friday after testing positive for drugs.
Sachenbacher-Stehle, who was competing in the biathlon in Sochi but did not win a medal, tested positive for the stimulant methylhexanamin with the second sample tested on Friday.
"The (German Olympic Committee) DOSB stands for a doping-free sport and a zero tolerance," said DOSB Secretary General Michael Vesper. "We only want clean performances. Every doping case is initially a disappointment but also proof that the system works."
Sachenbacher-Stehle, provisionally banned for five days before the start of the Turin 2006 Olympics for high levels of haemoglobin in her blood, won gold in the team sprint free event at the 2010 Vancouver Olympics and 4x5km relay at the 2002 Salt Lake City Games.
The 33-year-old, who also won silver in the 4x5km relay in Turin, narrowly missed out on medals in Sochi, coming fourth in the 12.5km mass start and the mixed relay.
"This is the worst nightmare you could imagine," she told German media. "I can't explain how the doping test could be positive."
Frullani, a police officer by profession, was dropped from the team due to compete on Sunday after testing positive for the substance dymetylpentylamine, and left the village.
The substance, identified as a stimulant in the World Anti-Doping Agency code, can be found in nasal decongestants.
Italian team officials said they had got a green light from the International Olympic Committee to replace Frullani, who had switched from track and field to bobsleigh in 2012, in their four-man bobsleigh team competing on the last day of the Games.
"The Italian Olympic Committee (CONI) now needs to sort out the composition of the bobsleigh team which Frullani was part of, to make it back up to four," CONI said in a statement.
They have requested that the athlete be replaced by the reserve Samuele Romanini and clearance for this has been received from the IOC.
The two cases mean the Sochi Games have had more positive tests than the Vancouver 2010 Olympics, where only one athlete was caught for using banned substances.
The IOC said before the Olympics it was planning to carry out 2,453 tests during the Games, including 1,269 pre-competition controls, which is a record for a Winter Olympics.
It has also increased pre-Olympic testing in the months leading up to the event so as to stop cheats from getting to the Games.
All Olympic medallists are tested as well as several other finalists, while hundreds more targeted tests are conducted based on intelligence.
Samples taken at the Sochi Olympics will be stored for a decade and re-tested in line with the new World Anti-Doping Code that comes into effect on Jan. 1, 2015.
Germany, who are fourth in the medals table with eight golds and 16 medals in total, sent a total of 154 athletes to Sochi. Italy, who have yet to win gold in Sochi, sent 114 athletes. (Additional reporting by Julien Pretot and Annika Briedthardt in Rosa Khutor; editing by Mike Collett-White)