Will Carling has urged England to omit Sam Burgess from their World Cup squad after warning Stuart Lancaster that his lack of union experience will be exposed by top opposition.
Burgess is competing with Luther Burrell for a place alongside first choice centres Brad Barritt and Jonathan Joseph in the hosts' 31-man party, which is announced on Thursday lunchtime.
The 26-year-old swapped league for union 10 months ago and made his Test debut in the 19-14 victory over France 12 days ago, executing two bit tackles in a solid if unspectacular display.
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Carling, speaking at Heineken's World Cup campaign launch, insists he feels "sorry" for Burgess for being fast tracked into the England set-up.
"I'm in awe of Sam as a rugby league player, but there is no one that I have spoken to who I respect - ex-players, coaches - who thinks he's ready," the former England captain and centre said.
"I don't understand what the rush is and it's unfair on him. I feel sorry for him. If he wants to make it in union, there's plenty of time.
"He's been playing union for 10 months and half of that was in a different position to what England are playing him in.
"He'll hit you hard if he can line you up and he's a great guy, but I don't believe he's one of the four best centres in England.
"He was functional against France and wasn't a disaster, but there was nothing that made me think 'wow'. I thought Henry Slade had a far bigger impact than Burgess with his touches and the way he read the game.
"If you watched Burgess carefully he was out of position a huge amount in defence and England can't afford that against sides who will focus on him.
"He hasn't had time in the game. He doesn't understand where the ball is coming from and you can see that in the way his feet are when he lines up.
"The southern hemisphere boys will focus on him if he's playing. If (Australia centre) Matt Giteau plays against him??he'll sucker him on for the big hit and opponents will be coming from angles he doesn't understand."
Carling also questioned Lancaster's decision to cut Danny Cipriani from the World Cup squad after the Sale playmaker had produced an inspired cameo from the bench in Saturday's 25-20 defeat in Paris.
"Coaches have to make calls, but Cipriani wasn't given a chance. He didn't get a start, he didn't even get a half," Carling said.
"In the 20 minutes he was given on Saturday, he was outstanding, but that doesn't seem to have mattered. Why was he even in the squad if they weren't going to give him a fair go? Any time he has had, he's been exceptional."