In January 1995, Greg made his Test debut for Australia against England in the Adelaide Oval in South Australia; scoring a century on his debut match. He followed that with a century in the WACA Ground in Perth during his second match and scored a century at Edgbaston in England in 1997 and scoring three centuries in his first three Ashes Test series. He also represented the national team in One Day International matches. During his peak, he batted with aggression and he was effective against both fast bowlers and spinners.
He was particularly strong square of the wicket, which was rewarded on his home ground, the Adelaide Oval, where the square boundaries are shorter. He was also an effective medium pace bowler (average bowling speed 125 km/h). His highest Test match score was 214 runs, against South Africa in Johannesburg in South Africa. Most of those runs were achieved with his former team mate and captain, Steve Waugh, with whom he was involved in one of the highest batting partnerships in cricket when the pair scored 385 runs together, batting for an entire day's play without losing a wicket