Kobe - England are set to have both wing Jack Nowell and prop Mako Vunipola available for the first time this Rugby World Cup when their campaign continues against Argentina next week.
Nowell has been sidelined with ankle ligament damage while Vunipola, brother of England No 8 Billy, has aggravated an old hamstring injury.
"You want your best players fit and they trained well. Mako is world class and Jack is also world class," England wing Jonny May told reporters in Kobe on Friday after a squad workout.
"To get two world-class players back raising the standard of everyone around them and having those options for Eddie (Jones, the England head coach) is brilliant at this stage."
England attack coach Scott Wisemantel added: "They are good... At this stage, we believe everyone will be available for selection."
Wisemantel, asked about Nowell's qualities, replied: "He does offer something different and he is a hybrid really - a winger come back rower with the way he plays.
"Mako gives us something with our ball-carrying and energy around the park. But he will find it difficult to get back into the team because the boys are doing a good job."
England, however, could be without Piers Francis after the centre was cited Friday for a high tackle soon after the kick-off of their 45-7 win over the United States in Kobe on Thursday that left Eagles fullback Will Hooley concussed.
The 2003 world champions, England now have a maximum 10 points from their opening two Pool C matches after starting this World Cup with a 35-3 bonus-point win over Tonga.
But they are expected to face a significant step up when they play Argentina in Tokyo on October 5.
"Two tricky ones," said Wisemantel of the games against Tonga and the USA.
"They are playing for their lives. That is the first part of the tournament over and we are two down and we move to next week and that is the Argentina game."
The Pumas have long been known for their scrum power but Wisemantel said there was much more to their game now than setpiece strength.
"They have threats all across the park," the Australian explained. "You have your spiritual leaders like Agustin Creevy, but you also have guys who can really open a game up like Emiliano Boffelli at fullback, a very good player.
"There is a lot of experience - Nicolas Sanchez knows how to move his team around the field, also Tomas Cubelli at halfback - they are a really good team."