A New South Wales and Australian representative wing , he played club football for the Parramatta Eels with whom he won four NSWRL premierships.
Grothe's size, speed and trademark ability to break a tackle through sheer strength enabled him to perfectly book-end Parramatta's star studded backline of the early 1980s outside Brett Kenny, Mick Cronin, Peter Sterling and Steve Ella.
He débuted in first grade 1979, however after a promising start which included three tries in one game against South Sydney, a succession of injuries meant that he was not able to show his full ability until the 1981 season.
Queensland fullback Colin Scott fielded a kick near halfway and split the defence in a 45-metre charge that ended just short of the line thanks to a despairing tackle by Grothe who had made almost 10 metres on him.
The Guru was member of Parramatta's victorious premiership side in 1982, but didn't play in any of the 1982 State of Origin series games.
He was prominent in the Eels side that won their third successive premiership, figuring in the 18-6 Grand Final victory over Manly-Warringah when in the 13th moment he steamrolled his way over burly Manly fullback Graham Eadie to score.
In the Australian season he suffered from knee problems that prevented his selection for the mid-season tour of New Zealand, but he was superb in Parramatta's end-of-season surge until they lost 0–26 to Canterbury in the Preliminary Final.
However injury restricted him to playing less than half the season, and while he was originally selected for the 1986 Kangaroo touring squad, and indeed he was involved in pre-tour promotional photo sessions with the team, Grothe was controversially ruled out with a knee injury before the team left for the tour and he was replaced by young Penrith Panthers halfback Greg Alexander.
When a best Australian team of the limited tackle era was named in 1995, Grothe shared with prop Arthur Beetson the distinction of being a unanimous choice of every judge.
They are thus one of several father and son pairs to play State of Origin, including Wayne and Mitchell Pearce, and Steve and Josh Morris/Brett Morris, all for NSW.