Taulupe Faletau could become one of Wales' "great players" if he signs a dual contract, according to former captain Michael Owen.
Faletau, 24, has been offered a dual contract by the Welsh Rugby Union.
The Newport Gwent Dragons number eight has not signed it yet, and Owen has urged him to do so.
"If he wants to be one of the great players of Welsh rugby, which he's on course to become, he needs to stay in Wales," said ex-Dragons skipper Owen.
"If he wants to be a top level international, there's no better place to be than Wales because of the way you get looked after.
"You play less games, you're monitored more effectively."
British and Irish Lions back-rower Faletau is one of the few Wales players based in their homeland who have not signed a dual contract.
Alun Wyn Jones, Dan Biggar, Scott Williams and Rhys Webb are among the high-profile squad members to have recently penned the deals.
Faletau has a year left on his current contract with the Dragons and has been linked with a move to English Premiership side Bath.
Dragons director of rugby Lyn Jones says he is "100%" confident the player will stay and, according to head coach Kingsley Jones, Faletau is "really happy" at Rodney Parade.
"Toby Faletau is an absolutely world-class, top drawer number eight," added Owen.
"Any club in the world would want to have him playing for them. He's a brilliant player."