Sponsored by Prima Solutions of Loughborough, the Prima Tiger Cup is a free-to-enter tournament for under-10s teams all hoping for the opportunity to play at the home of 10-time English champions Leicester Tigers before a first-team game.
There are five qualifying festivals this season, making this the biggest-ever season in the competition.
Teams from Braintree, Bury St Edmunds, Cambridge, Hadleigh, Haywards Heath, Ipswich YM, Peterborough Lions, Rushden and Higham, South Woodham Ferrers and hosts Newmarket took part in the fourth Prima Cup festival of the season.
The teams were split into two leagues with Braintree and Haywards Heath taking top spots after winning all of their games and scoring the most points.
Braintree and Haywards Heath will now go forward to the knockout stages to be played at Welford Road before the Leicester Tigers fixture against Heineken Cup rivals Montpellier in December.
Holt and North Walsham from Norfolk, plus Tamworth, Wolverhampton, Market Harborough, Ashby, Oadby Wyggestonians and Hinckley are among the clubs who have already qualified for the knockout stages.
The line-up for the next round will be finalised this weekend after the fifth festival hosted by Mellish RFC in Nottinghamshire.