Aged 20, Lillee made his first-class debut for Western Australia in 1969-70 and impressed with his raw pace. Lillee took 32 wickets in his debut season to be WA's leading wicket-taker. At the end of the season, he toured New Zealand with an Australian second team and took 18 wickets at 16.44 average.

Early Career

The following season, Lillee made his Test debut in the Sixth Test at Adelaide in the 1970-71 Ashes series, taking 5/84 from 28.3 eight-ball overs. His first Test wicket was John Edrich, caught by Keith Stackpole for 130, but it was not until the Seventh Test at Sydney that John Hampshire became the first batsman to be "caught Marsh, bowled Lillee". The following season, during the series against the Rest of the World XI, which had been arranged in place of the cancelled series against South Africa, Lillee announced himself during the first innings of the second unofficial "Test" match at his home ground in Perth, destroying a powerful batting lineup that included Garry Sobers, Clive Lloyd, Rohan Kanhai and Sunil Gavaskar to finish with 8/29 in only 7 overs, which would remain his career-best bowling figures in an innings. Sobers would later comment that as far as particular spells went, Lillee's bowling that day was the fastest he had ever faced. Lillee then backed up with 4/63 in the second innings to end with match figures of 12/92 as Australia won by an innings.

Lillee followed this performance with a successful Ashes tour of England in 1972, when he "asserted himself as a great bowler". In a series that ended 2–2, he was the outstanding bowler on either team, taking 31 wickets at an average of 17.67. This earned him selection as one of Wisden's five Cricketers of the Year for 1973.

Back injury

During a Test against Pakistan in the 1972–73 season, Lillee felt sharp pain in his back for the first time, but continued to play. On the tour of the West Indies that followed, Lillee broke down completely and was diagnosed with stress fracture in his lower vertebrae. Forced out of cricket, he spent six weeks during the winter of 1973 wearing a plaster cast that encased his entire torso. After the removal of the cast, he played club cricket in Perth as a specialist batsman.

There was speculation that his bowling career was nearly over. Lillee persevered, undergoing an intensive physiotherapy routine, formulated by sports scientist Frank Pyke, and remodelling his bowling action. In 1974–75, he returned to Test cricket for the Ashes series and was paired with New South Wales fast bowler Jeff Thomson to form one of the most effective opening bowling combinations in Test cricket. The pair was a major factor in Australia's emphatic 4–1 victory. In 1975, the University of Western Australia timed