Vidal became the second consecutive Manchester City youngster to sign on loan for Grimsby Town in as many seasons, following the signing of Shaleum Logan at the same time in the previous season.
He signed on an initial one month loan at Grimsby on the 1st September 2008, he was meant to sign 3 days previously but returned to Manchester following a Friday training session in Grimsby.Vidal made his professional debut in the clubs 2-2 draw with Chesterfield in the Football League Trophy 1st Round at Saltergate. He was used as a second half substitute, and the club went on to win 4-1 in the penalty shoot out. He made his league debut on the 6th September against Gillingham as a second half sub for Jamie Clarke. Vidal returned to the Eastlands after playing a total of five games for Grimsby in all competitions.
"Jav reminds me of Earl Barrett in many ways - he's a rubber man who bounces all over the place with great athleticism.. He's played for England under 19s this year and, like the rest of the lads, he will benefit immensely from playing alongside senior players" said Jim Cassell in the Official Manchester City annual 2008