Steven broke into the Hibernian first team just after his 17th birthday. He became a regular for the Edinburgh team, scoring 43 goals in 156 appearances, including two against Kilmarnock in the 2007 Scottish League Cup final. He joined Burnley in June 2009 for a club record £3 million before moving to Wolves a year later, for another club record fee of £6.5 million. In August 2012, he signed for Sunderland. The towering striker was Scotland's top goalscorer in the UEFA Under-19 Championships in 2006, netting nine goals as Scotland finished as runners-up. Fletcher scored five times for Scotland under-21s between 2007 and 2008, and made his senior debut in a 1-1 friendly draw against Croatia in March 2008. He netted his first senior goal in a 2-1 FIFA World Cup qualifying win over Iceland in April 2009.Steven became the first player to score a hat-trick for Scotland since Colin Stein in 1969 when he scored three against Gibraltar in Euro 2016 qualification at Hampden. He would repeat the feat away to Gibraltar (the match was actually played in Faro, Portugal) in the last game of the campaign.