Navy News
Direct from the front-line, the official newspaper of the Royal Navy, Navy News, brings you the latest news, features and award winning photos every month.
The Sub Lt, who is the Education Officer for Taunton-based 40 Commando, beat her Army opponent from the Royal Logistics Corps.
"She was a bit more experienced and she was a little bit heavier than me, so I was quite lucky that I got to put some weight on before the fight,” said Rebecca.
"There was a lot of pressure in front of my colleagues to do well, so I was quite nervous going in."
"I don't think I've ever been hit so hard in my life, so at first it was a bit of shock but I think I eased into it in the second and third rounds and kind of got into my stride a bit later in the fight."
She's going to go up [with] the [Royal] Navy squad to the England development camp and the England women's team are going to have a look at her and see how she gets on up there
Warrant Officer Class 2 Wilf Rees
As a result, she's been offered the chance to train alongside the England team.
40 Commando's boxing coach, Warrant Officer Class 2 Wilf Rees, said:
"She's going to go up [with] the [Royal] Navy squad to the England development camp and the England women's team are going to have a look at her and see how she gets on up there.
"She's only had four bouts [and] she's won them all. Her boxing skills are fantastic."
"She needs to move her head more so she doesn't get caught with so many shots on the nose! But it's all stuff we can work with."
It didn't happen, however, without plenty of training.
Back at the gym in Norton Manor Camp S/Lt Carman's been keeping up the momentum with the rest of the squad, as the only female on the team.
It's something she relishes. She told us: "It was pretty intense training. Sprinting in the morning, sparring in the afternoon. So it takes a lot of commitment, I think.”
Direct from the front-line, the official newspaper of the Royal Navy, Navy News, brings you the latest news, features and award winning photos every month.