The 21-year-old, who was an unused substitute in the games against Hull City, Stoke City and Newcastle United in the Premier League, has joined Russell Slade’s side as they look to finish a largely disappointing season on a good note.
Once described as 'the next Sol Campbell', as pointed out by Wales Online, Ajayi has earned the plaudits during his time in North London but has never looked like a serious contender for a first-team slot in Arsene Wenger’s side.
Earlier in the year, he went on trial with Sunderland and starred in a 0-0 draw with Norwich but nothing materialised. The failed trial paved the way for the youngster to join the former Premier League side, who are fighting for a respectable top half finish in the Championship.
Cardiff are currently 14th in the league on 51 points, just two back from 12th placed Sheffield Wednesday.
Although Ajayi hasn't lived up to expectations at Arsenal, the youngster seems like a good fit for the Welsh side, and the Championship, as he looks to get his senior career up and running with a strong finish to the season.
The Bluebirds still have Leeds United, Ipswich Town and Nottingham Forest to play in their final seven games so will be able to offer a good challenge for Nigerian youth international.