Krajicek started playing tennis at the age of three. She feels equally comfortable on all surfaces, her favorite shot is the serve.
Krajicek made her debut at the Wimbledon junior tournament on July 1, 2003, twelve days after her half-brother Richard left professional tennis . In the first round she defeated Kristina Czafikova, who was almost four years her senior , 6: 4, 3: 6, 6: 1. In the individual competition she made it through to the third round. In doubles, she and her Czech partner Kateřina Böhmová made it into the final, in which they were defeated by the pairing Alissa Kleibanowa / Sania Mirza 6: 2, 3: 6, 2: 6.
Michaëlla Krajicek celebrated her greatest success so far in 2004 at the US Open by winning the junior title. On September 12, 2004 she defeated the American Jessica Kirkland in the final there with a clear 6-1, 6-1.
Over the years she has developed more and more into a dual specialist. In addition to the six tournament wins in doubles, the WTA Tour has also made eleven finals. In 2014 she was in the semifinals of a Grand Slam tournament for the first time at the French Open . She repeated the good result in doubles 2015 at the Australian Open .
She has been playing for the Dutch Fed Cup team since 2004 . Their record shows 17 wins and 15 defeats.