Cycling star Gino Mader has tragically died ... succumbing to serious injuries he suffered in a horrifying crash at the Tour de Suisse on Thursday.
Mader's team, Bahrain Victorious, announced the sad news Friday morning ... explaining the Swiss rider was initially hurt after he lost control of his bike while traveling at a high rate of speed on a downhill portion of the race's Stage 5.
Tour de Suisse organizers said Mader tumbled into a ravine as a result of the wreck ... and when medical personnel first found him, he was laying motionless in a body of water.