Brian O'Driscoll has admitted his Lions team-mate Jamie Roberts will be a "big threat" when Ireland take on Wales on Saturday.
O'Driscoll and Roberts forged a formidable partnership during the 2009 Lions tour to South Africa.
However they will be on opposite sides for the RBS Six Nations encounter at the Millennium Stadium.
And O'Driscoll knows only too well what his Irish team-mates will be up against.
"Jamie's a talented footballer, a great ball carrier and a big, hard physical guy who uses his size really well," said O'Driscoll.
"He's the sort of guy who accelerates into tackles and knows what his power can do.
"He's definitely a player of a very high calibre and getting better with each Test he plays. He's a big threat."
O'Driscoll has also hailed another of the Lions contingent in the Wales side - with the Ireland captain claiming Shane Williams is one of the world's top wingers.
"Wales really tick when Shane Williams is playing well for them," he said.
"He gets his hands on the ball a hell of a lot more than most international wingers and he has big moments in big games for them."