Durham chief executive David Harker says England will find it tough to beat South Africa without a rejuvenated Steve Harmison in the side.
Harmison was included in the squad after a sparkling return to form with his county this season, but he missed the final cut for the third Test at Edgbaston on Wednesday.
The 29-year-old has found his pace and control of old but he was still omitted from the England side as Peter Moore went for just four bowlers against the Proteas - who lead 1-0 in the series.
Harker says that England will find it tough to win without Harmison - who has 41 first-class wickets under his belt this season.
"I'm disappointed for Steve that he's not in the side. He has bowled extremely well for us all season and we've been delighted with his form," Harker said.
"We have seen enough of him this year to know that it will be difficult for England to win without him.
"I'm sure it will only be a question of time before he's back in the England side."
Skipper Michael Vaughan said that it was a close call to leave out Harmison, as Paul Collingwood and Ryan Sidebottom returned to the side.
Harmison could be in line for a Test return at the Oval next month on a wicket that traditionally should offer him pace and bounce to work with.
"He was very close (to playing) and that's why we brought him into the squad - it's a sign for him that we feel he's got a chance of getting get back in," confirmed Vaughan.
"He's obviously not in the XI this week, but who's to say he won't be in the XI at The Oval the week after?"
Former England chairman of selectors Ray Illingworth believes that Harmison will have to do more to work his way back into the side - after so long out of form.
"It's a difficult decision to make but you might as well keep him [Harmison] out of the side if the pitch isn't right for him," Illingworth said.
"Harmison had two years where he didn't perform for England and I don't think he can just walk back into the side.
"The lads that have been bowling have been playing well over the last 12 months.
"I don't think he's been badly treated by the selectors. He's got to fight for his place. He's not actually been all that good from what I've seen of him."