Jones hails Saints star Ludlam and discusses Francis incident after England win
Ludlam rounded off a fantastic all-round display with a second-half score in a 45-7 success in Kobe.
The 23-year-old finally established himself at Franklin's Gardens last season, having emerged from the Saints Academy.
Advertisement
Hide AdAdvertisement
Hide AdAnd he is now living the dream on the international stage, playing in both of England's World Cup matches so far.
"He's an incredible young player and he's only going to get better," said Jones after seeing his side run in seven tries against the USA.
"He was lucky to make Northampton's B team 12 months ago and he's out here in a World Cup and one of the most impressive young forwards out there."
Piers Francis also impressed for England after being given a start at inside centre.
Advertisement
Hide AdAdvertisement
Hide AdBut he could find himself in hot water with the citing officer after a hit on former Saints back Will Hooley in the opening seconds of the match.
"We leave that up to the referee," Jones said.
"We're quite happy whatever the judicial process is to take part in it.
"We've got no qualms one way or the other.
"Whatever way it goes, we'll support the decision by World Rugby."