The 21-year-old, from Waterlooville, will represent England at the World Amateur Team Championships playing 72 holes over the Iberostar Playa Paraiso and Mayakoba El Camaleion golf clubs.
Achieving selection to the team for Mexico was the main target for the Corhampton golfer who is the world number seven.
He said: ‘The selection for Mexico means a lot to me.
‘It was my main goal for the season to be selected for it.
‘My sports psychologist Laurence and I set a goal to be selected for all England and Great Britain & Ireland representative matches this year and we’ve achieved that.
‘I think having him as my mind coach this year has contributed to me performing well on the course.
‘We have a few days to familiarise ourselves with the two courses and work out our game plan for the week.’
Play gets under way in Mexico a week today.
Gregory’s England team-mates are Brabazon Trophy winner Jamie Bower, from Yorkshire, and Kent’s Alfie Plant, winner of the Lytham Trophy, back in May.
The Mayakoba course was designed by Australian Greg Norman.
The 7,039 yard course winds it way through three distinct landscapes – from tropical jungle to dense mangroves with stretches of sand along the oceanfront location bisected by massive limestone canals.
It was the first Mexican course to host an official PGA Tour event and the first held outside North America and next week the world’s finest amateurs will battle it out for glory.
Gregory has been doing his home work on the course after taking a two-week break from competitive golf before a stringent practice with his coach Simon Andrews, from the Portsmouth Golf Centre, over the last week.
He only made his full England debut in the win over France at Formby, in May, and made his GB&I debut in the St Andrews Trophy win over Europe at Prince’s, in August.
Now he will be hoping to go one better than England’s Ryder Cup stars Paul Casey and Luke Donald by helping his country to land the Eisenhower Trophy.
Up until 2002, a Great Britain and Ireland team contested the biennial Eisenhower Trophy and were crowned champions on four occasions – the last in 1998, in Chile.
In 2000, Casey and Donald were both hot-shot college golfers based in the United States and were joined in the three-man team by another future Ryder Cup player Jamie Donaldson.
But they were pipped to the title at Berlin’s Sporting Club by an American team, including Ben Curtis who went on to win the Open in 2003.