Early career Born in Paris, France, N'Diaye began his career with US Vandœuvre in
Vandœuvre-lès-Nancy. At the age of 14, he moved across the
arrondissement to join the biggest club in the region, AS Nancy. Upon arrival, Alfred endured early struggles, but quickly gained noticed following his second season at the academy. In 2006, he signed his first professional contract.
Nancy N'Diaye made his debut in the squad during the
2007–08 season in the
Coupe de la Ligue, at the age of 17, coming on as a halftime substitute for
Frédéric Biancalani in a 3–0 loss to
Lens. That was his only appearance that season as he would be relegated back to the
reserves helping a young Nancy reserve squad barely avoid relegation. Following the season, N'Diaye earned promotion to the senior squad for the
2008–09 season. He was assigned the number 29 shirt and made his league debut in the opening match of the season against
Lille appearing as a substitute in a 0–0 draw. Two months later, he earned his first league start in a 1–1 draw against
Paris Saint-Germain. His positive play earned him regular starts in the squad, including playing the full 90 minutes in the club's 3–0 upset victory over
Olympique de Marseille at the
Stade Vélodrome and playing, on two occasions, 120 minutes of football in cup play against
Grenoble in the Coupe de la Ligue and
SO Romorantin in the
Coupe de France. In total, he made 27 appearances and collected 7 yellow cards.
Bursaspor On 1 July 2011, Nancy confirmed on its website that the club had reached an agreement with Turkish club
Bursaspor for the transfer of N'Diaye. The deal was finalised on 3 July for a reported fee of €2 million.
Sunderland On 9 January 2013, it was announced that
Sunderland had completed the signing of N'Diaye for an undisclosed fee. He was given the number 4 shirt. On 12 January 2013, N'Diaye made his Sunderland debut at the
Stadium of Light in a match which they won 3–0 against
West Ham United. He came on as a substitute for
Adam Johnson and almost scored with his first touch in English Football as his shot went just wide. His full debut for Sunderland came against Wigan away, in which he produced a "wonderful" assist for
Steven Fletcher to score and put them in front.
Eskişehirspor (loan) On 28 July 2013 it was announced N'Diaye would join Turkish club Eskişehirspor on a season-long loan. On 28 January 2014, Eskişehirspor announced that N'Diaye's loan had been terminated by the club.
Betis On 30 January 2014, N'Diaye joined Spanish side
Real Betis on loan for the remainder of the
2013–14 campaign. He appeared in 16 matches, as the
Andalusians were relegated. On 22 August 2014,
free agent N'Diaye signed a five-year deal with the
Béticos.
Villarreal On 8 July 2016, N'Diaye signed a five-year contract with
Villarreal CF also in the main category.
Hull City (loan) On 31 January 2017, N'Diaye moved on loan to
Hull City for the remainder of the 2016–17
Premier League season. N'Diaye made his debut and scored the first goal in a home 2–0 victory over
Liverpool. Despite impressing during his 15 games at the club, N'Diaye was unable to keep Hull in the Premier League.
Wolverhampton Wanderers (loan) On 31 August 2017, the transfer deadline day of the 2017/18 summer transfer window, N'Diaye completed a last-gasp loan deal (with the option of a permanent move) to
English Championship club
Wolverhampton Wanderers. He made his debut for the club on 9 September 2017, coming on as a substitute in a 1–0 win against
Millwall. He scored his first goal for the club on 23 September 2017 in a 2–1 win against
Barnsley after coming on as a substitute. He played 36 games for Wolverhampton Wanderers in all competitions, as he helped the club win the EFL Championship title and gain promotion to the Premier League.
Málaga (loan) On 10 August 2018, N'Diaye moved on loan to
Málaga for the 2018–19
Segunda División season.
Al-Shabab On 30 August 2019, N'Diaye moved to Saudi club
Al-Shabab FC on a three-year contract. On 24 August 2022, N'Diaye was released from his contract.
Noah On 1 February 2024,
Armenian Premier League club
Noah announced the signing of N'Diaye. ==International career==