Harlequins director of rugby John Kingston would be "very surprised" if England prospect Marcus Smith is picked by Eddie Jones in the near future.
Smith made his second appearance in a Red Rose training squad when the RBS 6 Nations champions gathered in Oxford at the start of the week and despite Jones' attempts to dampen expectations of the 18-year-old, excitement is growing over his potential.
Four sparkling appearances for Quins in his breakthrough season have illustrated why he is held in such high regard, but Kingston believes the autumn series against Australia, Argentina and Samoa is too soon to blood him in the Test arena.
"I'd be very surprised if Eddie believes Marcus is ready to play international rugby. He's only played four league games for us," said Kingston, speaking at the Champions Cup launch at the Ricoh Arena.
"I understand the interest in Marcus because he's young, although he's not the first 18-year-old to be playing Premiership rugby.
"He'll get on well with England in the way he's got on well every time he's been asked to play by us.
"It's not some sort of gimmick whereby he's been selected because he's young.
"I don't give a rats how young he is, I give a rats about what he's able to do and therefore also what's the right thing to do in looking after him.
"Marcus will jump at every opportunity he gets. I keep talking about his ability, but his greatest strength is here (points to head).
"It's the maturity that impresses me most and because of that I've no doubt that he will stand up and face any challenge head on."
Harlequins and former Australia captain James Horwill believes Smith has a bright future ahead of him - as long as he is allowed to mature at his own pace.
"Marcus is so composed for an 18-year-old and that's the most impressive aspect of his game," Horwill said.
"Everyone can see the skill that he's got - the ability to pass, beat defenders and take the ball to the line.
"He's not a big guy but he's very brave. He's calm under pressure and can control individuals around him.
"The exciting thing is that he will get a lot better. At the moment he's only scratching the surface.
"We must allow him to develop his rugby. He's an 18-year-old kid who loves playing rugby and that's the way we want to keep it."
Meanwhile, Saracens could sign a player on a short-term contract to combat the back-row injury crisis that has accounted for Billy Vunipola, Schalk Burger and Michael Rhodes.
"We're assessing who is out there and if there's someone suitable then it's possible we could bring someone in," director of rugby Mark McCall said.
"We've got some good young back rows at the club, but number eight is an area where we're potentially weak.
"Maro (Itoje) can't play at eight but he will probably play back row a lot over the next few weeks."