[8] Isimat-Mirin's progress led to him being called up to Valenciennes’ first team, appearing as an unused substitute against Bordeaux on 28 April 2010.

[19] However in a match against Evian on 3 December 2011, Isimat-Mirin was sent–off in the 16th minute for a professional foul on Yannick Sagbo, as Valenciennes lost 2–1.

[21] Isimat-Mirin scored his second goal of the season, in a 2–0 win against Le Mans in the first round of the Coupe de France.

[23] After serving a one match suspension, Isimat-Mirin returned to the starting line–up against Dijon on 4 February 2012 and helped Valenciennes win 2–1.

[26] At one point, Ligue 1 side Lille agreed to sign the player but the move was broken down over the transfer price.

[29] In the January transfer window, Isimat-Mirin was linked with a move to Paris Saint-Germain and Lille, whose 2.5 million euros was rejected by the club.

[32] He made his return to the starting line–up for Valenciennes against Toulouse on 23 February 2013 and helped the club keep a clean sheet, in a 0–0 draw.

[33] However in a match against Bastia on 30 March 2013, Isimat-Mirin suffered a knee injury and was substituted in the 63rd minute, as Valenciennes lost 4–3.

On 28 June 2013, Isimat-Mirin left Valenciennes to join the newly promoted Ligue 1 side AS Monaco on a four–year contract for a transfer fee costing 4 million euros.

"[37] Having appeared on the substitute bench for the next four months, Isimat-Mirin made his debut for AS Monaco, starting the whole game, in a 1–0 loss against Reims in the third round of the Coupe de la Ligue.

[44] Having appeared on the substitute bench, he made his debut for the club, starting the whole game, in a 2–0 win against Utrecht on 25 September 2014.

"[46] A month later on 18 October 2014, Isimat-Mirin made his league debut for PSV Eindhoven, starting the whole game and kept a clean sheet, in a 3–0 win against AZ Alkmaar.

[48] Isimat-Mirin said that once his loan spell at PSV Eindhoven ends, he will return to his parent club and fight for his first team place at AS Monaco.

[49] Following the absence of Jeffrey Bruma, Isimat-Mirin received a number of first team starts, playing in the centre–back position for the next seven matches.

[52] After serving a one match suspension, he returned to the starting line–up in the right–back position against ADO Den Haag and helped PSV Eindhoven win 3–2 in the last game of the season.

[53] His contributions to the season saw PSV Eindhoven win the league title for the first time since 2008 after beating SC Heerenveen 4–1 on 22 April 2015; it was the first major trophy of his professional career.

With the club wanted to keep him, it was announced on their website on 26 June 2015 that he signed a four-year contract on a permanent basis.

Ahead of the 2016–17 season, PSV Eindhoven's technical director Marcel Brands said that he's expecting Isimat-Mirin to receive first team football following the departure of Bruma.

[68] He made his return to the starting line–up against Bayern Munich in the UEFA Champions League match on 19 October 2016, coming on as a 61st-minute substitute, as PSV Eindhoven lost 4–1.

Ahead of the 2017–18 season, Isimat-Marin was linked a move away from PSV Eindhoven, as clubs, such as, 1899 Hoffenheim and Nice were interested in signing him.

Ahead of the 2018–19 season, Isimat-Mirin was told by the new manager Mark van Bommel that he can leave the club after being deemed surplus of requirement.

[85] As a result, Isimat-Mirin found his first team opportunities limited, appearing a number of matches on the substitute bench.

[87] However because of lack of first team opportunities, manager van Bommel expected the player to leave PSV Eindhoven in the January transfer window.

"[90] Isimat-Mirin made his debut for Beşiktaş, starting the whole game and kept a clean sheet, in a 3–0 win against Akhisarspor on 18 January 2019.

[99] Following his loan spell at Toulouse ended, Isimat-Mirin continued to be linked a move away from the club, as Zulte Waregem and Hatayspor were interested in signing him.

[104][105] Having appeared in the substitute bench for the next three matches since joining the club, he made his Toulouse debut against Nîmes Olympique on 21 September 2019 and started the whole game, in a 1–0 loss.

[108] After missing one match due to suspension, Isimat-Mirin returned to the starting line–up against Lyon in the last 16 of the Coupe de la Ligue, as the club lost 4–1 on 18 December 2019.

[111] However, his return was short–lived when the LFP elected to end the season early due to the coronavirus pandemic, resulting in the club's relegation.

[113] A couple days later, Isimat-Mirin signed a two-year contract with Major League Soccer side Sporting Kansas City.

[4] In April 2019, he became a first time father when his wife Kimberly Mirin, gave birth to a baby girl named Azaya.