Jofra Archer, Mark Wood and Chris Woakes are locked in a battle for a spot in England's bowling attack for the third Test with South Africa.
Fielding coach Paul Collingwood revealed the trio were all in contention to replace the injured James Anderson in Port Elizabeth.
With the series tied at 1-1, the tourists will hope to build on their impressive 189-run victory in the second Test, with Archer, Wood and Woakes eyeing a spot in the line-up.
"They've an opportunity over the next two training sessions to prove to us they should be the one in the team," said Collingwood.
"It's actually really nice to be able to come into a Test being able to choose from players who are 100 per cent ready to go.
"Here at PE [Port Elizabeth] it's generally a slower pitch, so sometimes having that kind of X-factor can be great.
"Sunday's training session was one of the best we've had for a long time.
"We saw bowlers really running in against the batters. They were really making it difficult for them. If we can do that more often, then our education as a team will grow very strongly and very quickly."
Responding to suggestions that Archer had lost his way after bursting onto the scene with England last year, Collingwood jumped to the 24-year-old's defence.
"He's very early on in his international career," he said. "He hasn't bowled a lot with the Kookaburra ball, which requires a completely different skillset from the Dukes.
"His main skill is bowling 90 miles per hour plus. We have enough bowlers in and around the county circuit who can bowl at 82 to 85 miles per hour and try to nip it around.
"You want the likes of Wood and Archer to give you that X-factor.”
The third Test begins on Thursday.