Defence coach Kevin Sinfield believes Sinckler is ready to return at full match fitness, with England looking to usher players back to hit the ground running.
Tom Curry was backed to start against Argentina last weekend despite missing the entire August warm-up programme through ankle trouble.
And England’s conditioning coaches have pulled off a similar result with Bristol prop Sinckler, who is now raring to go, and fully available for selection.
“He’s worked incredibly hard, he’s been in the team sessions now for the last couple, he joined at the back end of last week,” said Sinfield.
“He's fit and ready to go and I think having spoken to [head of strength and conditioning] Aled Walters you understand the work they do behind the scenes with the guys who are injured. They’ve done an incredible job with Kyle, so he’ll be ready to go.”
Sinckler was a key figure in Eddie Jones’ England tenure and will be itching to get back to his best now, with veteran Dan Cole back and Bath’s Will Stuart also in the squad.
“Kyle works incredibly hard, he’s a great character who makes people laugh and if selected he deserves his spot,” said Sinfield.
“Competition for places is really good at this moment in time. With people who have been injured or suspended, them coming back is really important for us moving forward.
“The best teams I’ve played in and worked with have had competition for places and great depth, and when we are fully fit and when all 33 are available, there’s a wonderful amount of competition for places there.”
England’s medical and conditioning department were able to bring lock Ollie Chessum back ahead of schedule last month, after his ankle dislocation in March.
The Leicester second row was right back to his aggressive best in Saturday’s 27-10 win over Argentina that opened England’s Pool D account in fine fashion.
Sinfield added that Walters has brought together a team and a plan that can give England an edge.
“It’s big to have players back at full speed so quickly, and it’s a big rap for Aled, a big rap for Tom Tombleson and the team behind that, the medical team,” he said.
“They’ve done an incredible job with all the players that have been injured, they’ve all come back ahead of time, and match fit.”