After struggling to establish himself for New South Wales thereafter, Jaques transformed his career by signing for the English County Championship side Northamptonshire in 2003.

He was prolific, hitting over 1200 runs including a double century and returned to NSW an established member of the Pura Cup Champions.

2003/04 saw the consolidation of Jaques' English form in Australia as he built a reputation of being a player who could score quickly but also occupy the crease for many hours.

With Matthew Hayden and Justin Langer established at the top of the Australian batting lineup, Jaques himself did not rule out qualifying to become an English player.

In 2005–06, a timely century in the Pura Cup followed three consecutive centuries in the ING Cup for New South Wales, and Jaques was selected for the Australian squad for the 2nd Test against South Africa starting on Boxing Day, 2005 in Melbourne after regular opener Justin Langer pulled a hamstring in the previous match.

[4] Making his One-Day International debut for Australia against South Africa, Jaques made 94, falling six runs short of his maiden century.

One year later, and following the retirement from international cricket of Justin Langer, Jaques was called up to the Test squad for the home series against Sri Lanka ahead of his rival for the place, Western Australia's Chris Rogers, in part due to a fluent second innings 167 in a Pura Cup match against Western Australia in which Rogers scored 9 and 17.