Myall, who has represented England Saxons, is one of the shrewdest lineout operators in England where he dominated the lineout in the Aviva Premiership last season.
Huddersfield-born Kearnan joined the Leeds Academy at the age of 15 and two seasons made his first team debut off the bench against Sale Sharks in the Powergen Cup.
He appeared 127 times for Leeds and scored 12 tries before crossing the Pennines along with Carnegie club mates Luther Burrell, Hendre Fourie and Scott Mathie to join the Sharks. In his final campaign for Leeds, he made 28 appearances and played the full 80 minutes in all except seven of those games.
Kearnan joined Sale Sharks in 2011, made 21 appearances for them in the Premiership last season and was one of their stand-out performers.
Follow Kearnan on Twitter @KearnanMyall