Swindon Town Born in
Plymouth,
Devon, Morrison was a keen sportsman as a teenager, playing football and competing in athletics events. He favoured the
long jump and represented his county and the South-West England team in the event. At the age of fourteen, he gave up athletics due to the travelling involved and to focus on his football career. Morrison joined his hometown club
Plymouth Argyle in 2006, playing in the club's youth system for a year. However, he was released by Plymouth at the age of sixteen after being told by coaches that he "didn't use (his) size well enough." He subsequently joined
Swindon Town in the summer of 2007, after being spotted by youth team manager
Paul Bodin, signing an 18-month professional contract in February 2008, before being promoted to the first team in March 2008. Swindon manager
Maurice Malpas commented that he would like to see Morrison and fellow youth player
Ben Joyce gain first team experience, and Morrison made his professional debut on 26 April 2008 against
Gillingham at the age of seventeen, coming on as a first-half substitute for
Jerel Ifil during a 1–1 draw. He made his first start for Swindon on the final day of the season, 3 May 2008, in a 2–1 victory over
Millwall. The following season, Morrison featured more frequently in the first team, making 23 appearances in all competitions and scored his first goal for the club on 25 October 2008, in a 2–0 league victory against
Oldham Athletic. His performances led to several requests from
Premier League sides to take Morrison on trial, which were rejected by Swindon, with new Swindon manager
Danny Wilson describing him as "the future of the club." Morrison also won the club's Young Player of the Year award. Having struggled to break into the first team at the start of the
2009–10 season, with
Gordon Greer and
Scott Cuthbert being preferred, He made his debut for Southend in a 1–0 defeat against
Yeovil Town, being sent off for the first time in his career after 34 minutes for a professional foul. The loan deal was extended in December. Southend hoped to extend his loan in January 2010, although he eventually returned to Swindon later that same month after being recalled. Southend manager
Steve Tilson later expressed his frustration over the decision, stating that "I'm not going to hide the fact that we're very disappointed." During his loan spell, Morrison appeared eight times for Southend but made only four further appearances for Swindon during the remainder of the season. At the start of the
2010–11 season, Morrison was restored to the first team at Swindon with manager Danny Wilson praising Morrison's maturity at the start of the campaign. Having displaced
Lecsinel Jean-François in defence, Morrison scored five times in the first half of the season, including a goal against his former club Plymouth in the
FA Cup.
Reading in 2013 On 14 January 2011, Swindon Town and
Reading reached an agreement to transfer Morrison after a release clause in the player's contract was activated, with the deal completing four days later. Although the fee was officially undisclosed, it was reported to be between £250,000 and £300,000. Having failed to make an appearance for the club since signing, on 23 March 2011, he joined
Huddersfield Town on loan until the end of the season, with Reading retaining 24-hour recall after the first month. Huddersfield had shown an interest in signing Morrison before his move to Reading, with the player favouring a move to his parent club. Signed as cover for the central defensive partnership of
Peter Clarke and
Jamie McCombe, Morrison was an unused substitute in four matches for Huddersfield but, after failing to make an appearance while on loan, Reading recalled Morrison from Huddersfield on 19 April. Despite never playing for the club, Huddersfield manager
Lee Clark commented that he was "gutted" to lose Morrison, describing him as "a very good footballer and has shown a terrific attitude all the time." He made his Reading debut in a 2–1 defeat against
Charlton Athletic in the second round of the
League Cup on 23 August 2011, scoring a consolation goal in his first appearance for the club.
Huddersfield Town (loan) On 24 January 2012, Morrison re-joined Huddersfield Town on loan until the end of the season. He made his debut four days later in their 1–1 draw against
Tranmere Rovers at
Prenton Park and scored his first goal for the club in a 3–3 draw away to
Bury on 3 March. Morrison made 19 appearances during the regular league season, helping Huddersfield finish in fourth place and qualify for the
play-offs. He played in both legs of the club's 3–2 semifinal aggregate victory over
Milton Keynes Dons and scored in the
play-off final penalty shoot-out against
Sheffield United, which Huddersfield won, With parent club Reading having been promoted to the Premier League, Morrison stated that he would be open to a permanent move to Huddersfield.
First team After returning to Reading, Morrison's first appearance in the
2012–13 season came in a 3–2
League Cup victory over
Queens Park Rangers (QPR) on 26 September where he came on as a second-half substitute. He then started against
Arsenal in the next round on 30 October in a game which Reading lost 7–5. On 2 October, he signed a new four-year deal with Reading. He made his Premier League debut against QPR on 4 November 2012, helping the side record their first clean sheet of the season in their following match, a 0–0 draw with
Norwich City. He scored his first league goal against
Wigan Athletic two weeks later. After dropping out of the side midway through the season, Morrison finished the campaign in a defensive partnership alongside
Adrian Mariappa under new manager
Nigel Adkins. He finished the campaign with sixteen appearances in the Premier League as Reading suffered relegation back to the Championship after a single season. In August 2013, Morrison was handed the Reading captaincy in the absence of regular captain
Jobi McAnuff. He described the event as "an honour". On 10 December 2013, Morrison extended his contract with Reading until the summer of 2017. In November 2014, Morrison suffered a serious knee injury after damaging ligaments during a 1–1 draw with Queens Park Rangers. The injury kept him out for five months, making his return in a 1–1 draw with former club Huddersfield Town. He finished the season with 21 league appearances as Reading missed out on a play-off place on the final day of the season.
Cardiff City in 2015 On 15 August 2014, Morrison signed a four-year contract with fellow Championship side
Cardiff City for an initial fee of £3 million, with further add-ons based on appearances and future promotions. He made his debut for Cardiff four days later in a 1–0 victory against Wigan Athletic. Morrison opened his account for Cardiff scoring the opener in a 2–1 win over
Sheffield Wednesday before scoring a brace against
AFC Bournemouth. Morrison was handed the captain's armband at the start of the
following season, in the absence of club captain,
David Marshall. Morrison was ever-present in Cardiff's starting eleven before suffering a knee injury during a 1–0 loss to
Birmingham City on 19 December 2015, which was initially expected to rule him out for a month. However, his return was delayed until 5 March 2016, when he came on in place of
Lee Peltier in a 2–0 win against
Severnside rivals
Bristol City. Morrison saw Cardiff miss out on a play-off place after losing to
Sheffield Wednesday, before receiving an operation, meaning he would miss the final game of the season and potentially the start of the
next season. Morrison returned in time for the new season and was named as captain in Cardiff's 1–0 loss to
Bristol Rovers in the
EFL Cup. In September, he was named as permanent club captain by manager
Paul Trollope, following the sale of David Marshall. Morrison made a career-high 46 appearances, scoring four goals during the season. runner-up trophy with manager
Neil Warnock. During summer 2017, fellow Championship club, Sheffield Wednesday, submitted a £3 million bid for Morrison, which manager
Neil Warnock stated "wouldn't even buy one of Morrisons legs", and an improved £5 million bid. Morrison later stated that he had no intention of leaving the club and committed to Cardiff, signing a three-year contract. His first goal of the season, against
Sheffield United, led Cardiff to win their three opening games of the season, for the first time in their history. In February, Morrison scored three goals in five games, as well as helping his side record three
clean sheets, which led to him being nominated for
EFL Championship Player of the Month. Morrison was named Cardiff City Player of the Year as he captained the side to second place in the Championship, winning promotion to the Premier League. During the season, he made 43 appearances in all competitions, scoring a career-high seven goals, and his defensive partnership with
Sol Bamba conceded jointly the fewest goals in the league and recorded 19 clean sheets. Morrison suffered a broken nose during a 2–1 victory over
Brighton & Hove Albion in November 2018 but rejected the chance to have surgery to rectify the injury, instead choosing to postpone the operation in order to keep playing. In January 2019, Morrison was admitted to hospital and underwent emergency surgery to remove a burst appendix. He had been suffering from severe pain in his abdomen and was instructed to go to hospital by Cardiff City club doctor Len Noakes who had been contacted by Morrison's wife after Morrison had refused to seek treatment. It was reported that Morrison was told that he had been "45 minutes from death." Prior to his operation, he had been ever-present in the Premier League for Cardiff, having started all 22 matches to that point. He remained sidelined for six weeks, before making his return in a 5–1 defeat to
Watford on 22 February, and finished the season with 35 appearances in all competitions as Cardiff suffered relegation to the Championship. In February 2022 he was injured, ruling him out for the season, with the club directors to meet to discuss his future. By July 2022 his contract had expired, and he was undergoing rehabilitation for his injury. Having recovered from his injury, Morrison departed the club in January 2023.
Rotherham United On 10 January 2023, he signed for Championship club
Rotherham United on a short-term deal until the end of the season. He was released by the club at the end of the 2023–24 season. ==International career==