19-year old Myrie-Williams is a left-winger and has already spent three months of this season on loan at League One Cheltenham Town, making five league appearances for the club.
After making his debut in May 2005, the England U-19 international has gone on to make 48 career appearances and last season he scored the winner in Bristol City's 3-2 win over Tranmere at Ashton Gate.
He has pace to burn and is a natural left-sided player. Ronnie Moore described him as "A pacy winger who likes to run with the ball and take on defenders".
Jennison joins other left-sided loanee's Kevin Cooper and Andrew Taylor on loan at the club and is sure to provide stiff competition for a place on the Rovers left.