He was called up to play for the England national team during his time at Portman Road, and went on to represent his country at the 1980 European Championships and the 1982 World Cup.

He joined Major League Soccer club New England Revolution in 2004 as a member of Steve Nicol's coaching staff.

He succeeded Paul Sturrock as the club's manager two months later before returning to his role as head coach upon the arrival of Peter Reid.

Mariner started his career as an amateur player at non-league club Chorley, close to his Lancashire roots and his style at the helm of their attack caught the attention of Plymouth Argyle, for whom he signed in 1973.

[10] Mariner made his debut in September 1976[11] and quickly settled into the Ipswich side as an old-fashioned number 9 – i.e., a forward capable of taking hard tackles and rough treatment from defenders but willing to give it back, while also scoring a fair share of goals.

[12] Such was Mariner's impact that six months after joining Ipswich, he made his England debut as a substitute in a 5–0 win over Luxembourg at Wembley and played from the beginning in the following game against Northern Ireland in the British Home Championship at Windsor Park, Belfast.

[8] By now, Mariner had become one of a number of 'target man'-type centre forwards for England coach Ron Greenwood to select from, with Stuart Pearson and Bob Latchford also on the scene.

[8] He did not play in the opening 1–1 draw versus Belgium in Turin but came on as a substitute in the remaining two group matches – a defeat against Italy and a victory over Spain, which ensured England's elimination from the competition.

England began their qualifying campaign for the 1982 World Cup with a conclusive 4–0 win over Norway, with Mariner scoring a superb goal with a deft turn and shot from 25 yards.

But in the five final England warm-up matches prior to the World Cup in Spain, he scored four times, including a stunning solo run and strike against the Netherlands at Wembley.

England went into a 2–1 lead thanks to a brace from Bryan Robson – the first of which was one of the World Cup Finals' quickest-ever goals – before Mariner slammed home a close-range volley to complete an impressive 3–1 win.

Mariner's club boss Robson subsequently became England coach and he continued to select him as the qualification campaign for the 1984 European Football Championship got underway.

Making his Arsenal-debut at Highbury against Aston Villa on 18 February in a 1-1 draw, he scored his first goal at Nottingham Forest the next week.

[17] With Hateley in the ascendancy and Mariner regularly sidelined at Arsenal, Robson opted not to select him for the England squad which qualified for Mexico 1986.

[citation needed] Meanwhile, at his club Mariner was rarely on the field, he was blighted by an Achilles heel injury which saw him only play nine times in 1985–86, including matches as an emergency centre half.

[28][29] In 2004, he was hired by the New England Revolution of Major League Soccer as assistant coach to former Liverpool and Scotland defender Steve Nicol.

[31] He was interviewed by MLS expansion side Seattle Sounders FC for their head coach role prior to their inaugural season in 2009.

It was announced the following day, 18 October 2009, that he was to become the new head coach of Plymouth Argyle, with Paul Sturrock staying on as team manager.

[33] On 10 December 2009, Mariner replaced Sturrock as manager of Plymouth Argyle, following a run of poor form which left the Pilgrims second bottom in the Championship.

"[39] Mariner was named Director of Player Development for Toronto FC on 6 January 2011, joining new head coach Aron Winter at the club.

[40] After starting the season with 9 straight losses, Winter stepped down as Toronto named Mariner as the new head coach on 7 June 2012.

[42] The club rebounded briefly under the new coach, but after "a dismal 0-10-4 run in league play" to end the 2012 season,[29] Mariner was dismissed on 7 January 2013.