Saracens boss Mark McCall said on Saturday former England captain Owen Farrell could return to the club next season as injury cover.
Farrell has experienced a disappointing debut season with French club Racing 92, sparking reports he wants to move back to the English Premiership by ending his contract a year early.
Saracens are permitted to bring in a reinforcement to fill the gap created in the squad by Alex Lozowski's Achilles injury, which will sideline him until Christmas.
That raises the prospect of Farrell rejoining his only English club, although McCall admitted there are several hurdles to be navigated before a deal could be completed.
The 33-year-old, plagued by a groin injury this season, has to be paid the same as Lozowski and Saracens must reach agreement with Racing 92 over a transfer fee.
"We think we're a bit vulnerable at 10," said McCall, whose side failed to qualify for the Premiership play-offs despite a 36-26 victory over Bath on Saturday.
"The way the process works is you compile a list of people you think might be suitable.
"Owen wasn't on the list because he's under contract with Racing, but there are some noises that Racing might be prepared to look at that and he might be prepared to look at that as well.
"A couple of things have to happen. One, Racing have to let him go and they've got to let him go for a price which a club is willing to pay. And secondly he's got to accept a salary which is less than he's on.
"If Owen comes on to the list, he looks like a pretty good option on the list because of the value for money that he would bring."
Farrell spent 16 years at Saracens before heading to France in 2024.
McCall believes England's record points scorer, who has played 112 times for his country, would provide a vital service by helping develop Saracens' young fly-halves Fergus Burke and Louie Johnson.
"It's not just about having talent, it's about being able to think properly on the field. Owen's obviously one of the best at that," McCall said.
"Owen and Louis Johnson in particular have a very strong relationship already. They talk every month at least.
"Owen's so willing to share his knowledge and his experience with younger players. For our young talents who are developing, it could be a great thing to have him there."