McFadden started his playing career with Motherwell, where he came to prominence in the 2002–03 season by scoring 19 goals and winning the Scottish PFA Young Player of the Year award.

McFadden came to greater prominence during the 2002–03 Scottish Premier League SPL season, scoring 19 goals from 34 starts and winning the Young Player of the Year Award.

[8][9] In this season Motherwell finished bottom of the SPL and should have been relegated but were given a reprieve due to First Division champions Falkirk not meeting stadium criteria.

This scoring run of form continued the next week versus Aston Villa, a half-volley from just outside the area helping the Toffees to a 4–1 victory [13] and ended the season with seven goals.

[14] McFadden made an indifferent start to the 2006–07 season, following the arrival of record signing Andrew Johnson, managing only two goals in the first half of the campaign.

[16] After nearly three months on the sidelines, he made a scoring return to action for Everton as a second-half substitute versus Charlton Athletic on 15 April 2007.

[18] He dedicated his goal against Middlesbrough on 2 January 2008 to the recently deceased Phil O'Donnell, by pointing to his black armband and then to the sky in tribute to the former Motherwell captain.

[19] On 18 January 2008, McFadden joined Birmingham City on a three-and-a-half-year deal, with an option for additional two years, for an initial fee of £5 million, potentially rising to £6m depending on appearances.

[20][21] McFadden's first goal arrived in his fourth game for the club, a penalty kick versus West Ham United at Upton Park, after he had been fouled by Lucas Neill.

[22] In his next match, at home to Arsenal, he scored from a 20-yard free kick before adding the equalising goal from the penalty spot in the last minute of stoppage time.

[23] McFadden scored Birmingham's first goal of the 2009–10 Premier League season, a 92nd-minute penalty, to give the club a 1–0 home win against Portsmouth.

[34][35] Again out of contract, McFadden trained with Motherwell during the 2012–13 pre-season,[36] playing for the club in a testimonial match for Steven Hammell on 21 July 2012 against Everton.

[46] In a 4–2 defeat versus Newcastle United in a friendly match, McFadden scored a penalty with an audacious chip down the centre of the goal, known as a Panenka.

[62] Two months later, he entered negotiations to be the marquee player of Indian Super League club Kerala Blasters, after the departure of Carlos Marchena.

[73] McFadden gained his first Scotland cap at the age of 19 against South Africa on a Far East tour, at the end of which a night out drinking caused him to miss his flight home.

[74] Despite his domestic performances he became a regular in Berti Vogts' Scotland set-up, scoring his first goal against the Faroe Islands during a 3–1 win in a UEFA Euro 2004 qualifying match at Hampden Park on 6 September 2003.

[75] McFadden's goal versus Netherlands in November 2003 gave Scotland a famous 1–0 victory,[76] although they then lost 6–0 in Amsterdam and failed to qualify for UEFA Euro 2004.

[83][84] McFadden was substituted at half-time in a UEFA Euro 2012 qualification match against Liechtenstein in September 2010, and was criticised by manager Craig Levein after the game.

[85] In March 2013 new Scotland manager Gordon Strachan said that he would consider McFadden for selection, but noted that he needed to play regularly at club level, having not done so in the previous two seasons.