[4] Jackson made his Newcastle debut as a substitute for Ian Stewart in a 2–1 defeat at home to Arsenal on Saturday 18 October 1986, in which he won a penalty for his side.
After being ruled out for six months of his first campaign with a broken ankle which initially went undetected,[5] Jackson spent four years at Tannadice, picking up a 1990–91 Scottish Cup runners-up medal and finishing that season as the club's top scorer with 18 goals.
[11] In October, he was barred from playing for Hearts due to the impending trigger of a clause enforcing a one-year extension to his contract,[12] seeing him discuss a possible return to former club Dundee United.
[13] After United signed Charlie Miller instead,[14] Jackson negotiated a deal to return to first-team action at Hearts,[15] only to find himself surplus to requirements when Craig Levein was appointed three weeks later.
Making his début in March 1995, Jackson was also in the starting line-up for a fixture against Estonia in Tallinn in October 1996, but a scheduling dispute meant the home team did not adhere to a quickly-rearranged afternoon kick-off time, and the match was abandoned at kick-off with no caps awarded to the Scotland players; the fixture was re-arranged for the following February, but Jackson was not selected.
Despite Jackson's earlier vow to move into management,[11] he became an SFA agent[27] representing players including fellow Scots Jackie McNamara, Mark Wilson and Steven Thompson.
[28] In February 2013, Jackson relinquished his agent status to join client and former Celtic teammate McNamara – recently appointed as manager of Dundee United – as a coach.