In March 2008 Groot competed in her home country at the 2008 European Aquatics Championships where she finally became European Champion in the 50 m butterfly beating teammate Inge Dekker in the final, after having won the bronze medal four times in this event. In the 100 m butterfly she finished up 5th and qualified for the 2008 Summer Olympics. She started in the heats of the 4×100 m freestyle and 4×100 m medley but was replaced for the finals each time. In the second week of April she participated in the 2008 FINA Short Course World Championships in Manchester. She started individually in the 100 m butterfly and reached a 6th place. She also swam in the heats of the 4×100 m medley but was replaced in the final by Inge Dekker. The Olympic Games in Beijing were a disappointment because she ended 30th in the 100 m butterfly.