On 4 August, Tielemans made his Ligue 1 debut in the 3–2 home win over Toulouse, coming on as a substitute for Radamel Falcao in the 87th minute.
He made his UEFA club competition debut for Monaco on 13 September in the UEFA Champions League group match away to RB Leipzig, playing the full 90 minutes and registering his first competitive goal for Monaco by equalizing in a 1–1 draw.
On 16 September, Tielemans made his first Ligue 1 start and played the entire match in the 3–0 home win over Strasbourg, after having played a total of 56 minutes as a substitute in his first four Ligue 1 matches.
France Football named Tielemans in their lists of the biggest flops of the first half of the season and the season overall.
1997
Youri Marion A. Tielemans (born 7 May 1997) is a Belgian professional footballer who plays as a midfielder for club Aston Villa and the Belgium national team.
Tielemans began his career at Anderlecht, where he made 185 official appearances and scored 35 goals across four seasons.
2013
On 21 July 2013, he was included in the senior squad for the first time, remaining an unused substitute in the 1–0 win over Genk in the 2013 Belgian Super Cup.
On 28 July 2013, he made his first-team debut in the opening round of the Belgian Pro League season against Lokeren, replacing injured Sacha Kljestan after 25 minutes of a 2–3 home loss.
This made him the fourth-youngest player in the league's history.
On 2 October 2013, he became the youngest Belgian player to play in the UEFA Champions League, starting in a match against Olympiacos at the age of 16 years and 148 days.
2014
He played 29 games – of which 21 starts – as Anderlecht won the 2013–14 Belgian Pro League, scoring to open a 3–0 win over Club Brugge at the Constant Vanden Stock Stadium on 6 April 2014, a game in which he also assisted Cyriac.
Tielemans won the Belgian Young Player of the Year award in each of his first two seasons.
2015
In June 2015, Tielemans was called up to the senior Belgium squad for a UEFA Euro 2016 qualifier against Wales.
2016
Tielemans represented Belgium at several youth levels and before gaining his first cap for the national team in November 2016, aged 19.
Tielemans scored 13 times in 37 Belgian First Division A matches as Anderlecht won the 2016–17 Belgian First Division A.
He scored 5 goals in 15 2016–17 UEFA Europa League matches, with his club reaching the quarter-finals, and was selected in its Squad of the Season.
He finally made his senior international debut on 9 November 2016, in a 1–1 friendly away draw to rival Netherlands, replacing Steven Defour in the 82nd minute.
2017
He won the league title twice and in 2017 was chosen as the Belgian Professional Footballer of the Year.
He is the youngest Belgian to play in the UEFA Champions League, making his debut in the competition at the age of 16 years and 148 days.
He won the 2017 Ebony Shoe Award for best player of African origin, and was named 2016–17 Belgian Professional Footballer of the Year.
On 24 May 2017, Tielemans joined 2016–17 Ligue 1 champions Monaco on a five-year deal for a fee of around €25 million.
He made his competitive debut on 29 July in the Trophée des Champions at the Grand Stade de Tanger, playing the full 90 minutes in the 2–1 loss to Paris Saint-Germain and assisting Djibril Sidibé's opening goal.
2018
He was part of the squad that came third at the 2018 FIFA World Cup, also featuring at UEFA Euro 2020 and the 2022 World Cup.
Tielemans is a youth product of Anderlecht and signed his first professional contract with the club at the age of 16.
He scored his first Ligue 1 goal in his 31st game on 2 September 2018, in a 3–2 home loss to Marseille.
Tielemans was included in manager Roberto Martínez's 23-man squad for the 2018 FIFA World Cup in Russia.
He played four matches in the tournament, including the 2–0 win over England in the third-place match.
2019
After two years at Monaco in Ligue 1, he joined Leicester City in 2019, initially on loan and then for an estimated fee of £32 million.
He played 195 total games and scored 28 goals, including the only goal of the 2021 FA Cup final.
In 2023 he joined Aston Villa upon the expiration of his contract.
On 31 January 2019, Tielemans joined Premier League club Leicester City on loan until the end of the season, with Adrien Silva going the other way in a swap deal.
On 9 March, Tielemans scored his first goal for the club in a 3–1 win over Fulham.
Tielemans completed a permanent move to Leicester City on 8 July 2019, on a four-year deal for an estimated fee of £32 million.
He scored in a 3–1 home win over Bournemouth on 31 August, but courted controversy with a high challenge on Callum Wilson that escaped punishment even after consultation with the video assistant referee; referees' chief Mike Riley ruled that this was an incorrect decision and Tielemans should have been sent off.
On 15 May 2021, Tielemans scored the only goal of the 2021 FA Cup Final with a long-range strike against Chelsea in the 63rd minute, sealing Leicester's first ever FA Cup title.
He was named the man of the match.
On 10 June 2023, Premier League club Aston Villa announced that they had reached an agreement to sign Tielemans on a free transfer, upon the expiry of his Leicester City contract on 1 July.
He made his debut on 12 August in the season opener, a 5–1 loss at Newcastle United, in which he replaced the injured Leon Bailey at half time.
On 26 October 2023, Tielemans scored his first goal for Aston Villa in a 4–1 away UEFA Europa Conference League victory over AZ Alkmaar.
Tielemans scored his first senior goal for Belgium on 21 March 2019, in a UEFA Euro 2020 qualifying match against Russia.
