Auxerre Born in
Melun, Seine-et-Marne, Boly played youth football for three clubs, also having a three-year spell at the
INF Clairefontaine academy. He made his senior debut with
AJ Auxerre's reserves and, in February 2011, he signed his first professional contract after agreeing to a three-year deal with an option for a fourth. On 16 April 2011, Boly made his
Ligue 1 debut by playing the full 90 minutes in a 1–0 away win against
Toulouse. He scored his first goal in the competition the following matchday, in a 1–1 home draw to
Lens. Boly was an undisputed starter in the
2011–12 season (33 games, one goal), but the
AJA were relegated to
Ligue 2 after finishing last.
Braga On 1 September 2014, Boly moved to Portugal and joined
Braga on a four-year deal. He spent
his first season with
the B-team, in the
Segunda Liga.
Porto On 31 August 2016, Boly signed a five-year contract with
Porto with a €45 million buyout clause. He played only eight competitive matches during his spell, including the 1–0 away loss against
Juventus FC for
the last-16 stage of the
UEFA Champions League where he featured the second half after coming on as a
substitute for
André Silva.
Wolverhampton Wanderers On 8 July 2017, Boly joined
EFL Championship club
Wolverhampton Wanderers on a
season-long loan, reuniting him with his former head coach
Nuno Espírito Santo. He made his competitive debut for Wolverhampton on the opening day of
the 2017–18 season in a 1–0 home win against
Middlesbrough, and scored his first goal with them on 31 October to help Wolves win 2–0 away against
Norwich City. After making 37 official appearances and helping them achieve promotion, Boly signed a permanent contract with Wolves. He made his
Premier League debut on 11 August 2018, in a 2–2 home draw against
Everton. He scored his first goal in the competition two weeks later in a 1–1 home draw to
Manchester City, but the goal proved controversial as television replays showed the ball was deflected into the goal by his forearm after glancing off his head. Boly scored his first ever goal in UEFA European competition in Wolves's
2019–20 UEFA Europa League Group stage game against
Beşiktaş in Istanbul on 3 October 2019, a game that Wolves won 1–0. Boly fractured his left
fibula in training on 26 October 2019, necessitating surgery to insert a plate and screws on 30 October 2019. Boly returned from this injury in Wolves's 0–0 draw away to
Manchester United on 1 February 2020, although he had been an unused substitute in Wolves's previous Premier League fixture at home to
Liverpool on 23 January 2020. Boly scored his first goal of the
2020–21 season, and his first Premier League goal since the 2018–19 season, on 16 January 2021 against
West Bromwich Albion in the
Black Country derby. On 5 April 2021, after returning from playing with his national team in the
2021 Africa Cup of Nations qualifications, Wolves announced that Boly had caught
COVID-19, and was self-isolating in line with government guidance. Wolves's head coach, Nuno Espírito Santo, announced after Wolves's Premier League game with West Bromwich Albion on 3 May 2021 that Boly was suffering the effects of
long covid, ruling him out from appearing for Wolves in the game that evening. Boly would not feature for Wolves again until 19 May 2021, when he played the full 90 minutes of the away Premier League game at Everton.
Nottingham Forest On 1 September 2022, Boly signed with Premier League side
Nottingham Forest on a two-year deal for an undisclosed fee. On 5 June 2024, the club said the player had signed a one-year extension. ==International career==