Delhees, a left-hander, began playing Federation Cup tennis for Switzerland as a 17-year old in 1976.

Her doubles partnership with Christiane Jolissaint, which resulted in ten wins, is the most prolific in the Fed Cup for Switzerland.

From 1983 she was known as Petra Jauch-Delhees after marrying German Peter Jauch.

[2] She had her best performance at Grand Slam level when she upset sixth seed Manuela Maleeva in the first round of the 1984 US Open and made it to the round of 16 stage, despite entering the draw as a qualifier.

[3] In 1985 was runner-up to Kathy Horvath at the Palm Beach Cup and won the Spanish Open doubles with Patricia Medrado.