And a lot of that English talent currently resides at Franklin’s Gardens, where Jim Mallinder’s side have racked up an impressive eight-game winning run.

But World Cup winner Greenwood maintains the likes of Ashton, Foden and Clarke will still have to step their game a gear if they are to force their way past the established set-up.

“I have been very impressed by Northampton and especially by Jon Clarke, Ben Foden and Chris Ashton.

“They have all been doing very well recently but they will need five or six really strong performances over the next few weeks.

“You have to throw these guys in the deep end at some stage. There are 20 games to go until the World Cup so you have to give these players tests now or not at all.

“Martin Johnson is caught between a rock and a hard place at the moment. If you look at teams that win the World Cup – they have about 700 combined caps.

“But when he chooses wildcards he has to do some homework and give some game time beforehand.

“You want a settled team going into the World Cup so you would say this Six Nations is the last chance for guys to really establish themselves in the team.”

League convert Ashton has firmly found his feet at the top table of English rugby after a shaky first season in the Premiership.

After scoring 39 tries in National One, Ashton found life much more difficult last season only scoring one league try.

But the 22-year-old has recovered his confidence this campaign, averaging a try a game while full-back Foden is well in the hunt for the England No.15 shirt with Delon Armitage still working his way back to full fitness.

Yet Greenwood has tipped centre Clarke – who has had his game time limited by a string of injuries throughout his career – to be at the front of the queue.

While not possessing the all-action qualities that his midfield rivals can bring to the party, Greenwood maintains his calming influence is just what England were missing in the autumn.

He said: Jon struggled after coming back from injury and that was perfectly understandable.

“He has got a great centre partnership with James Downey. He is not quite making the buzz he was before his injury but he is getting close to that standard all the time.

“I think there is the notion that you need this unbelievable game breaker like Ma’a Nonu in midfield.

“Sometimes teams need a player who is like a concrete block in the midfield. Jon has strength, power and good hands.

“He might not be the glamorous option but the thing about his game is that he makes so few mistakes.

“When I watch him I almost never pick the wrong option and that is something England desperately needed in the autumn internationals.”