Leighton was one of the youngsters who was forced to step up into the first team quicker than expected after the club's administration in 2010.
By the end of the season the striker had played a huge part in Dundee's amazing run to overcome a 25 point deduction and remain in the 1st division.
There was reported interest from both sides of the Old Firm when he signed a two year deal at the beginning of the 2010/11 season. At that stage any thoughts of him making the first team must have been quite far off but the circumstances changed quickly during the season.
After going in administration Leighton became a regular feature on the bench before finally making his first team debut as a late sub against Morton in Dundee's 1-0 victory.
Another four short substitute appearances followed before Leighton was handed his first start away to Falkirk. Dundee came from behind to draw 2-2. Three days later Leighton played his first full 90 minutes at Dens against Dunfermline.
He continued his spell in the first team for another two games before a goal against Stirling indicated that Leighton had really arrived at this level.
On April 16th in a tough fixture away to Morton, Leighton looked every bit the ready first team striker as he netted twice in a 3-1 victory, seven days later he scored the only goal away to Ross County to confirm Dundee's 1st division status.
After such a good end to the season he was rewarded with a call up to the Scotland under 19s but unfortunately injury meant he could not travel with the squad.
He got another chance with the Scotland set up early in the new season, and scored his first international goal as the under 19s beat Wales in a UEFA Championship qualifier.
In the summer of 2011, he showed his commitment to Dundee by signing a new three year deal with the club.
2011/12 saw Leighton feature over twenty times, scoring his only goal of the season against Ayr United.
Leighton is on loan with Montrose for the 12/13 season.