Ben Stokes is to have a scan on a left knee injury despite playing a starring role as England clinched the one-day international series with South Africa.
Stokes was hampered by the problem in the first ODI at Headingley and, though he scored a century in Saturday's two-run win at the Ageas Bowl, he managed just three overs with the ball.
The all-rounder took one wicket for the loss of just 12 runs and conceded he is unsure as to the seriousness of the issue, which captain Eoin Morgan indicated will lead them to keep him out of the dead rubber at Lord's on Monday, with England set to take on Bangladesh in their Champions Trophy opener on Thursday.
"It comes and goes. I have bad days and good days," he told BBC Sport.
"I'm not sure if it is a worry or not, it might just be wear and tear. Hopefully we'll get a clearer picture.
"It's just the bowling. When I land on the floor I get a pain on the outside of my knee, so we just need to find out what that is.
"I was able to bowl, but at the end of my third over I started to feel it. It's a confidence thing as well. If I feel the knee I don't feel I'm running through the crease properly.
"I won't be wrapped cotton wool, it's just part of the game.
"We're managing it really well. The physio, doctor and I are doing all we can. Hopefully it will go away."
Morgan added: "I'm not worried. We're managing it as we go along.
"He played as a batter for us about a year ago when the same injury crept up. We did a very similar thing against Pakistan where he only bowled three or four overs. We built on it from there and then the injury went away.
"We're monitoring how it reacts after bowling, because it's bowling that aggravates it. He's crucial to our campaign, so hopefully we'll have a fit Ben Stokes for the Champions Trophy.
"He hates missing out, he always wants to be involved. With the form he's in, I won't be the one telling him he's not playing."